Replace GNU bc/dc with BSDL versions ported from OpenBSD. They have a good

compatibility level with the GNU counterparts and have shown to be mature
enough. For now, the GNU versions aren't removed from the tree, just detached
from the build.

Sponsored by:		Google Summer of Code 2008
Portbuild run by:	erwin
Approved by:		delphij

11 files changed, 4322 insertions, 0 deletions

diff --git a/usr.bin/dc/Makefile b/usr.bin/dc/Makefile
new file mode 100644
index 0000000..1ad72e0
--- /dev/null
+++ b/usr.bin/dc/Makefile
@@ -0,0 +1,13 @@
+#	$FreeBSD$
+#	$OpenBSD: Makefile,v 1.2 2006/11/26 11:31:09 deraadt Exp $
+
+PROG=	dc
+SRCS=	dc.c bcode.c inout.c mem.c stack.c
+LDADD=	-lcrypto
+DPADD=	${LIBCRYPTO}
+
+#SUBDIR+=	USD.doc
+
+WARNS?=	6
+
+.include <bsd.prog.mk>
diff --git a/usr.bin/dc/USD.doc/Makefile b/usr.bin/dc/USD.doc/Makefile
new file mode 100644
index 0000000..4a272a5
--- /dev/null
+++ b/usr.bin/dc/USD.doc/Makefile
@@ -0,0 +1,16 @@
+#	$FreeBSD$
+#	$OpenBSD: Makefile,v 1.2 2004/02/01 15:18:01 jmc Exp $
+
+DOC=	dc
+DIR=	usd/05.dc
+SRCS=	dc
+MACROS=	-ms
+BINDIR=	/usr/share/doc/papers
+
+paper.ps: ${SRCS}
+	${EQN} ${SRCS} | ${ROFF} > ${.TARGET}
+
+paper.txt: ${SRCS}
+	${EQN} -Tascii ${SRCS} | ${ROFF} -Tascii > ${.TARGET}
+
+.include <bsd.doc.mk>
diff --git a/usr.bin/dc/USD.doc/dc b/usr.bin/dc/USD.doc/dc
new file mode 100644
index 0000000..4caa0f4
--- /dev/null
+++ b/usr.bin/dc/USD.doc/dc
@@ -0,0 +1,753 @@
+.\"	$FreeBSD$
+.\"	$OpenBSD: dc,v 1.2 2003/09/22 19:08:27 otto Exp $
+.\"
+.\" Copyright (C) Caldera International Inc.  2001-2002.
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code and documentation must retain the above
+.\"    copyright notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed or owned by Caldera
+.\"	International, Inc.
+.\" 4. Neither the name of Caldera International, Inc. nor the names of other
+.\"    contributors may be used to endorse or promote products derived from
+.\"    this software without specific prior written permission.
+.\"
+.\" USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
+.\" INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT,
+.\" INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+.\" POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\"	@(#)dc	8.1 (Berkeley) 6/8/93
+.\"
+.EH 'USD:5-%''DC \- An Interactive Desk Calculator'
+.OH 'DC \- An Interactive Desk Calculator''USD:5-%'
+.\".RP
+.\" ....TM 75-1271-8 39199 39199-11
+.ND
+.TL
+DC \- An Interactive Desk Calculator
+.AU "MH 2C-524" 3878
+Robert Morris
+.AU
+Lorinda Cherry
+.AI
+.\" .MH
+.AB
+DC is an interactive desk calculator program implemented
+on the
+.UX
+time-sharing system to do arbitrary-precision
+integer arithmetic.
+It has provision for manipulating scaled fixed-point numbers and
+for input and output in bases other than decimal.
+.PP
+The size of numbers that can be manipulated is limited
+only by available core storage.
+On typical implementations of
+.UX ,
+the size of numbers that
+can be handled varies from several hundred digits on the smallest
+systems to several thousand on the largest.
+.AE
+.PP
+.SH
+.PP
+.ft I
+Editor's note: the description of the implementation details of DC in this
+paper is only valid for the original version of DC.
+The current version of DC uses a different approach.
+.ft
+.PP
+DC is an arbitrary precision arithmetic package implemented
+on the
+.UX
+time-sharing system
+in the form of an interactive desk calculator.
+It works like a stacking calculator using reverse Polish notation.
+Ordinarily DC operates on decimal integers, but one may
+specify an input base, output base, and a number of fractional
+digits to be maintained.
+.PP
+A language called BC [1] has been developed which accepts
+programs written in the familiar style of higher-level
+programming languages and compiles output which is
+interpreted by DC.
+Some of the commands described below were designed
+for the compiler interface and are not easy for a human user
+to manipulate.
+.PP
+Numbers that are typed into DC are put on a push-down
+stack.
+DC commands work by taking the top number or two
+off the stack, performing the desired operation, and pushing the result
+on the stack.
+If an argument is given,
+input is taken from that file until its end,
+then from the standard input.
+.SH
+SYNOPTIC DESCRIPTION
+.PP
+Here we describe the DC commands that are intended
+for use by people.  The additional commands that are
+intended to be invoked by compiled output are
+described in the detailed description.
+.PP
+Any number of commands are permitted on a line.
+Blanks and new-line characters are ignored except within numbers
+and in places where a register name is expected.
+.PP
+The following constructions are recognized:
+.SH
+number
+.IP
+The value of the number is pushed onto the main stack.
+A number is an unbroken string of the digits 0-9
+and the capital letters A\-F which are treated as digits
+with values 10\-15 respectively.
+The number may be preceded by an underscore _ to input a
+negative number.
+Numbers may contain decimal points.
+.SH
++  \-  *  %  ^
+.IP
+The
+top two values on the stack are added
+(\fB+\fP),
+subtracted
+(\fB\-\fP),
+multiplied (\fB*\fP),
+divided (\fB/\fP),
+remaindered (\fB%\fP),
+or exponentiated (^).
+The two entries are popped off the stack;
+the result is pushed on the stack in their place.
+The result of a division is an integer truncated toward zero.
+See the detailed description below for the treatment of
+numbers with decimal points.
+An exponent must not have any digits after the decimal point.
+.SH
+s\fIx\fP
+.IP
+The
+top of the main stack is popped and stored into
+a register named \fIx\fP, where \fIx\fP may be any character.
+If
+the
+.ft B
+s
+.ft
+is capitalized,
+.ft I
+x
+.ft
+is treated as a stack and the value is pushed onto it.
+Any character, even blank or new-line, is a valid register name.
+.SH
+l\fIx\fP
+.IP
+The
+value in register
+.ft I
+x
+.ft
+is pushed onto the stack.
+The register
+.ft I
+x
+.ft
+is not altered.
+If the
+.ft B
+l
+.ft
+is capitalized,
+register
+.ft I
+x
+.ft
+is treated as a stack and its top value is popped onto the main stack.
+.LP
+All registers start with empty value which is treated as a zero
+by the command \fBl\fP and is treated as an error by the command \fBL\fP.
+.SH
+d
+.IP
+The
+top value on the stack is duplicated.
+.SH
+p
+.IP
+The top value on the stack is printed.
+The top value remains unchanged.
+.SH
+f
+.IP
+All values on the stack and in registers are printed.
+.SH
+x
+.IP
+treats the top element of the stack as a character string,
+removes it from the stack, and
+executes it as a string of DC commands.
+.SH
+[ ... ]
+.IP
+puts the bracketed character string onto the top of the stack.
+.SH
+q
+.IP
+exits the program.
+If executing a string, the recursion level is
+popped by two.
+If
+.ft B
+q
+.ft
+is capitalized,
+the top value on the stack is popped and the string execution level is popped
+by that value.
+.SH
+<\fIx\fP  >\fIx\fP  =\fIx\fP  !<\fIx\fP  !>\fIx\fP  !=\fIx\fP
+.IP
+The
+top two elements of the stack are popped and compared.
+Register
+.ft I
+x
+.ft
+is executed if they obey the stated
+relation.
+Exclamation point is negation.
+.SH
+v
+.IP
+replaces the top element on the stack by its square root.
+The square root of an integer is truncated to an integer.
+For the treatment of numbers with decimal points, see
+the detailed description below.
+.SH
+!
+.IP
+interprets the rest of the line as a
+.UX
+command.
+Control returns to DC when the
+.UX
+command terminates.
+.SH
+c
+.IP
+All values on the stack are popped; the stack becomes empty.
+.SH
+i
+.IP
+The top value on the stack is popped and used as the
+number radix for further input.
+If \fBi\fP is capitalized, the value of
+the input base is pushed onto the stack.
+No mechanism has been provided for the input of arbitrary
+numbers in bases less than 1 or greater than 16.
+.SH
+o
+.IP
+The top value on the stack is popped and used as the
+number radix for further output.
+If \fBo\fP is capitalized, the value of the output
+base is pushed onto the stack.
+.SH
+k
+.IP
+The top of the stack is popped, and that value is used as
+a scale factor
+that influences the number of decimal places
+that are maintained during multiplication, division, and exponentiation.
+The scale factor must be greater than or equal to zero and
+less than 100.
+If \fBk\fP is capitalized, the value of the scale factor
+is pushed onto the stack.
+.SH
+z
+.IP
+The value of the stack level is pushed onto the stack.
+.SH
+?
+.IP
+A line of input is taken from the input source (usually the console)
+and executed.
+.SH
+DETAILED DESCRIPTION
+.SH
+Internal Representation of Numbers
+.PP
+Numbers are stored internally using a dynamic storage allocator.
+Numbers are kept in the form of a string
+of digits to the base 100 stored one digit per byte
+(centennial digits).
+The string is stored with the low-order digit at the
+beginning of the string.
+For example, the representation of 157
+is 57,1.
+After any arithmetic operation on a number, care is taken
+that all digits are in the range 0\-99 and that
+the number has no leading zeros.
+The number zero is represented by the empty string.
+.PP
+Negative numbers are represented in the 100's complement
+notation, which is analogous to two's complement notation for binary
+numbers.
+The high order digit of a negative number is always \-1
+and all other digits are in the range 0\-99.
+The digit preceding the high order \-1 digit is never a 99.
+The representation of \-157 is 43,98,\-1.
+We shall call this the canonical form of a number.
+The advantage of this kind of representation of negative
+numbers is ease of addition.  When addition is performed digit
+by digit, the result is formally correct.  The result need only
+be modified, if necessary, to put it into canonical form.
+.PP
+Because the largest valid digit is 99 and the byte can
+hold numbers twice that large, addition can be carried out
+and the handling of carries done later when
+that is convenient, as it sometimes is.
+.PP
+An additional byte is stored with each number beyond
+the high order digit to indicate the number of
+assumed decimal digits after the decimal point.  The representation
+of .001 is 1,\fI3\fP
+where the scale has been italicized to emphasize the fact that it
+is not the high order digit.
+The value of this extra byte is called the
+.ft B
+scale factor
+.ft
+of the number.
+.SH
+The Allocator
+.PP
+DC uses a dynamic string storage allocator
+for all of its internal storage.
+All reading and writing of numbers internally is done through
+the allocator.
+Associated with each string in the allocator is a four-word header containing pointers
+to the beginning of the string, the end of the string,
+the next place to write, and the next place to read.
+Communication between the allocator and DC
+is done via pointers to these headers.
+.PP
+The allocator initially has one large string on a list
+of free strings.  All headers except the one pointing
+to this string are on a list of free headers.
+Requests for strings are made by size.
+The size of the string actually supplied is the next higher
+power of 2.
+When a request for a string is made, the allocator
+first checks the free list to see if there is
+a string of the desired size.
+If none is found, the allocator finds the next larger free string and splits it repeatedly until
+it has a string of the right size.
+Left-over strings are put on the free list.
+If there are no larger strings,
+the allocator tries to coalesce smaller free strings into
+larger ones.
+Since all strings are the result
+of splitting large strings,
+each string has a neighbor that is next to it in core
+and, if free, can be combined with it to make a string twice as long.
+This is an implementation of the `buddy system' of allocation
+described in [2].
+.PP
+Failing to find a string of the proper length after coalescing,
+the allocator asks the system for more space.
+The amount of space on the system is the only limitation
+on the size and number of strings in DC.
+If at any time in the process of trying to allocate a string, the allocator runs out of
+headers, it also asks the system for more space.
+.PP
+There are routines in the allocator for reading, writing, copying, rewinding,
+forward-spacing, and backspacing strings.
+All string manipulation is done using these routines.
+.PP
+The reading and writing routines
+increment the read pointer or write pointer so that
+the characters of a string are read or written in
+succession by a series of read or write calls.
+The write pointer is interpreted as the end of the
+information-containing portion of a string and a call
+to read beyond that point returns an end-of-string indication.
+An attempt to write beyond the end of a string
+causes the allocator to
+allocate a larger space and then copy
+the old string into the larger block.
+.SH
+Internal Arithmetic
+.PP
+All arithmetic operations are done on integers.
+The operands (or operand) needed for the operation are popped
+from the main stack and their scale factors stripped off.
+Zeros are added or digits removed as necessary to get
+a properly scaled result from the internal arithmetic routine.
+For example, if the scale of the operands is different and decimal
+alignment is required, as it is for
+addition, zeros are appended to the operand with the smaller
+scale.
+After performing the required arithmetic operation,
+the proper scale factor is appended to the end of the number before
+it is pushed on the stack.
+.PP
+A register called \fBscale\fP plays a part
+in the results of most arithmetic operations.
+\fBscale\fP is the bound on the number of decimal places retained in
+arithmetic computations.
+\fBscale\fP may be set to the number on the top of the stack
+truncated to an integer with the \fBk\fP command.
+\fBK\fP may be used to push the value of \fBscale\fP on the stack.
+\fBscale\fP must be greater than or equal to 0 and less than 100.
+The descriptions of the individual arithmetic operations will
+include the exact effect of \fBscale\fP on the computations.
+.SH
+Addition and Subtraction
+.PP
+The scales of the two numbers are compared and trailing
+zeros are supplied to the number with the lower scale to give both
+numbers the same scale.  The number with the smaller scale is
+multiplied by 10 if the difference of the scales is odd.
+The scale of the result is then set to the larger of the scales
+of the two operands.
+.PP
+Subtraction is performed by negating the number
+to be subtracted and proceeding as in addition.
+.PP
+Finally, the addition is performed digit by digit from the
+low order end of the number.  The carries are propagated
+in the usual way.
+The resulting number is brought into canonical form, which may
+require stripping of leading zeros, or for negative numbers
+replacing the high-order configuration 99,\-1 by the digit \-1.
+In any case, digits which are not in the range 0\-99 must
+be brought into that range, propagating any carries or borrows
+that result.
+.SH
+Multiplication
+.PP
+The scales are removed from the two operands and saved.
+The operands are both made positive.
+Then multiplication is performed in
+a digit by digit manner that exactly mimics the hand method
+of multiplying.
+The first number is multiplied by each digit of the second
+number, beginning with its low order digit.  The intermediate
+products are accumulated into a partial sum which becomes the
+final product.
+The product is put into the canonical form and its sign is
+computed from the signs of the original operands.
+.PP
+The scale of the result is set equal to the sum
+of the scales of the two operands.
+If that scale is larger than the internal register
+.ft B
+scale
+.ft
+and also larger than both of the scales of the two operands,
+then the scale of the result is set equal to the largest
+of these three last quantities.
+.SH
+Division
+.PP
+The scales are removed from the two operands.
+Zeros are appended or digits removed from the dividend to make
+the scale of the result of the integer division equal to
+the internal quantity
+\fBscale\fP.
+The signs are removed and saved.
+.PP
+Division is performed much as it would be done by hand.
+The difference of the lengths of the two numbers
+is computed.
+If the divisor is longer than the dividend,
+zero is returned.
+Otherwise the top digit of the divisor is divided into the top
+two digits of the dividend.
+The result is used as the first (high-order) digit of the
+quotient.
+It may turn out be one unit too low, but if it is, the next
+trial quotient will be larger than 99 and this will be
+adjusted at the end of the process.
+The trial digit is multiplied by the divisor and the result subtracted
+from the dividend and the process is repeated to get
+additional quotient digits until the remaining
+dividend is smaller than the divisor.
+At the end, the digits of the quotient are put into
+the canonical form, with propagation of carry as needed.
+The sign is set from the sign of the operands.
+.SH
+Remainder
+.PP
+The division routine is called and division is performed
+exactly as described.  The quantity returned is the remains of the
+dividend at the end of the divide process.
+Since division truncates toward zero, remainders have the same
+sign as the dividend.
+The scale of the remainder is set to 
+the maximum of the scale of the dividend and
+the scale of the quotient plus the scale of the divisor.
+.SH
+Square Root
+.PP
+The scale is stripped from the operand.
+Zeros are added if necessary to make the
+integer result have a scale that is the larger of
+the internal quantity
+\fBscale\fP
+and the scale of the operand.
+.PP
+The method used to compute sqrt(y) is Newton's method
+with successive approximations by the rule
+.EQ
+x sub {n+1} ~=~ half ( x sub n + y over x sub n )
+.EN
+The initial guess is found by taking the integer square root
+of the top two digits.
+.SH
+Exponentiation
+.PP
+Only exponents with zero scale factor are handled.  If the exponent is
+zero, then the result is 1.  If the exponent is negative, then
+it is made positive and the base is divided into one.  The scale
+of the base is removed.
+.PP
+The integer exponent is viewed as a binary number.
+The base is repeatedly squared and the result is
+obtained as a product of those powers of the base that
+correspond to the positions of the one-bits in the binary
+representation of the exponent.
+Enough digits of the result
+are removed to make the scale of the result the same as if the
+indicated multiplication had been performed.
+.SH
+Input Conversion and Base
+.PP
+Numbers are converted to the internal representation as they are read
+in.
+The scale stored with a number is simply the number of fractional digits input.
+Negative numbers are indicated by preceding the number with a \fB\_\fP (an 
+underscore).
+The hexadecimal digits A\-F correspond to the numbers 10\-15 regardless of input base.
+The \fBi\fP command can be used to change the base of the input numbers.
+This command pops the stack, truncates the resulting number to an integer,
+and uses it as the input base for all further input.
+The input base is initialized to 10 but may, for example be changed to
+8 or 16 to do octal or hexadecimal to decimal conversions.
+The command \fBI\fP will push the value of the input base on the stack.
+.SH
+Output Commands
+.PP
+The command \fBp\fP causes the top of the stack to be printed.
+It does not remove the top of the stack.
+All of the stack and internal registers can be output
+by typing the command \fBf\fP.
+The \fBo\fP command can be used to change the output base.
+This command uses the top of the stack, truncated to an integer as
+the base for all further output.
+The output base in initialized to 10.
+It will work correctly for any base.
+The command \fBO\fP pushes the value of the output base on the stack.
+.SH
+Output Format and Base
+.PP
+The input and output bases only affect
+the interpretation of numbers on input and output; they have no
+effect on arithmetic computations.
+Large numbers are output with 70 characters per line;
+a \\ indicates a continued line.
+All choices of input and output bases work correctly, although not all are
+useful.
+A particularly useful output base is 100000, which has the effect of
+grouping digits in fives.
+Bases of 8 and 16 can be used for decimal-octal or decimal-hexadecimal
+conversions.
+.SH
+Internal Registers
+.PP
+Numbers or strings may be stored in internal registers or loaded on the stack
+from registers with the commands \fBs\fP and \fBl\fP.
+The command \fBs\fIx\fR pops the top of the stack and
+stores the result in register \fBx\fP.
+\fIx\fP can be any character.
+\fBl\fIx\fR puts the contents of register \fBx\fP on the top of the stack.
+The \fBl\fP command has no effect on the contents of register \fIx\fP.
+The \fBs\fP command, however, is destructive.
+.SH
+Stack Commands
+.PP
+The command \fBc\fP clears the stack.
+The command \fBd\fP pushes a duplicate of the number on the top of the stack
+on the stack.
+The command \fBz\fP pushes the stack size on the stack.
+The command \fBX\fP replaces the number on the top of the stack
+with its scale factor.
+The command \fBZ\fP replaces the top of the stack
+with its length.
+.SH
+Subroutine Definitions and Calls
+.PP
+Enclosing a string in \fB[ ]\fP pushes the ascii string on the stack.
+The \fBq\fP command quits or in executing a string, pops the recursion levels by two.
+.SH
+Internal Registers \- Programming DC
+.PP
+The load and store
+commands together with \fB[ ]\fP to store strings, \fBx\fP to execute
+and the testing commands `<', `>', `=', `!<', `!>', `!=' can be used to program
+DC.
+The \fBx\fP command assumes the top of the stack is an string of DC commands
+and executes it.
+The testing commands compare the top two elements on the stack and if the relation holds, execute the register
+that follows the relation.
+For example, to print the numbers 0-9,
+.DS
+[lip1+  si  li10>a]sa
+0si  lax
+.DE
+.SH
+Push-Down Registers and Arrays
+.PP
+These commands were designed for used by a compiler, not by
+people.
+They involve push-down registers and arrays.
+In addition to the stack that commands work on, DC can be thought
+of as having individual stacks for each register.
+These registers are operated on by the commands \fBS\fP and \fBL\fP.
+\fBS\fIx\fR pushes the top value of the main stack onto the stack for
+the register \fIx\fP.
+\fBL\fIx\fR pops the stack for register \fIx\fP and puts the result on the main
+stack.
+The commands \fBs\fP and \fBl\fP also work on registers but not as push-down
+stacks.
+\fBl\fP doesn't effect the top of the
+register stack, and \fBs\fP destroys what was there before.
+.PP
+The commands to work on arrays are \fB:\fP and \fB;\fP.
+\fB:\fIx\fR pops the stack and uses this value as an index into
+the array \fIx\fP.
+The next element on the stack is stored at this index in \fIx\fP.
+An index must be greater than or equal to 0 and
+less than 2048.
+\fB;\fIx\fR is the command to load the main stack from the array \fIx\fP.
+The value on the top of the stack is the index
+into the array \fIx\fP of the value to be loaded.
+.SH
+Miscellaneous Commands
+.PP
+The command \fB!\fP interprets the rest of the line as a 
+.UX 
+command and passes it to 
+.UX
+to execute.
+One other compiler command is \fBQ\fP.
+This command uses the top of the stack as the number of levels of recursion to skip.
+.SH
+DESIGN CHOICES
+.PP
+The real reason for the use of a dynamic storage allocator was
+that a general purpose program could be (and in fact has been)
+used for a variety of other tasks.
+The allocator has some value for input and for compiling (i.e.
+the bracket [...] commands) where it cannot be known in advance
+how long a string will be.
+The result was that at a modest
+cost in execution time, all considerations of string allocation
+and sizes of strings were removed from the remainder of the program
+and debugging was made easier.  The allocation method
+used wastes approximately 25% of available space.
+.PP
+The choice of 100 as a base for internal arithmetic
+seemingly has no compelling advantage.  Yet the base cannot
+exceed 127 because of hardware limitations and at the cost
+of 5% in space, debugging was made a great deal easier and
+decimal output was made much faster.
+.PP
+The reason for a stack-type arithmetic design was
+to permit all DC commands from addition to subroutine execution
+to be implemented in essentially the same way.  The result
+was a considerable degree of logical separation of the final
+program into modules with very little communication between
+modules.
+.PP
+The rationale for the lack of interaction between the scale and the bases
+was to provide an understandable means of proceeding after
+a change of base or scale when numbers had already been entered.
+An earlier implementation which had global notions of
+scale and base did not work out well.
+If the value of
+.ft B
+scale
+.ft
+were to be interpreted in the current
+input or output base,
+then a change of base or scale in the midst of a
+computation would cause great confusion in the interpretation
+of the results.
+The current scheme has the advantage that the value of
+the input and output bases
+are only used for input and output, respectively, and they
+are ignored in all other operations.
+The value of
+scale
+is not used for any essential purpose by any part of the program
+and it is used only to prevent the number of
+decimal places resulting from the arithmetic operations from
+growing beyond all bounds.
+.PP
+The design rationale for the choices for the scales of
+the results of arithmetic were that in no case should
+any significant digits be thrown away if, on appearances, the
+user actually wanted them.  Thus, if the user wants
+to add the numbers 1.5 and 3.517, it seemed reasonable to give
+him the result 5.017 without requiring him to unnecessarily
+specify his rather obvious requirements for precision.
+.PP
+On the other hand, multiplication and exponentiation produce
+results with many more digits than their operands and it
+seemed reasonable to give as a minimum the number of decimal
+places in the operands but not to give more than that
+number of digits
+unless the user asked for them by specifying a value for \fBscale\fP.
+Square root can be handled in just the same way as multiplication.
+The operation of division gives arbitrarily many decimal places
+and there is simply no way to guess how many places the user
+wants.
+In this case only, the user must
+specify a \fBscale\fP to get any decimal places at all.
+.PP
+The scale of remainder was chosen to make it possible
+to recreate the dividend from the quotient and remainder.
+This is easy to implement; no digits are thrown away.
+.SH
+References
+.IP [1]
+L. L. Cherry, R. Morris,
+.ft I
+BC \- An Arbitrary Precision Desk-Calculator Language.
+.ft
+.IP [2]
+K. C. Knowlton,
+.ft I
+A Fast Storage Allocator,
+.ft
+Comm. ACM \fB8\fP, pp. 623-625 (Oct. 1965).
diff --git a/usr.bin/dc/bcode.c b/usr.bin/dc/bcode.c
new file mode 100644
index 0000000..8b22008
--- /dev/null
+++ b/usr.bin/dc/bcode.c
@@ -0,0 +1,1781 @@
+/*	$OpenBSD: bcode.c,v 1.40 2009/10/27 23:59:37 deraadt Exp $	*/
+
+/*
+ * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <err.h>
+#include <limits.h>
+#include <openssl/ssl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "extern.h"
+
+BIGNUM		zero;
+
+#define __inline	
+
+#define MAX_ARRAY_INDEX		2048
+#define READSTACK_SIZE		8
+
+#define NO_ELSE			-2	/* -1 is EOF */
+#define REG_ARRAY_SIZE_SMALL	(UCHAR_MAX + 1)
+#define REG_ARRAY_SIZE_BIG	(UCHAR_MAX + 1 + USHRT_MAX + 1)
+
+struct bmachine {
+	struct stack		 stack;
+	u_int			 scale;
+	u_int			 obase;
+	u_int			 ibase;
+	size_t			 readsp;
+	bool			 extended_regs;
+	size_t			 reg_array_size;
+	struct stack		*reg;
+	volatile sig_atomic_t	 interrupted;
+	struct source		*readstack;
+	size_t			 readstack_sz;
+};
+
+static struct bmachine	 bmachine;
+static void		 sighandler(int);
+
+static __inline int	 readch(void);
+static __inline void	 unreadch(void);
+static __inline char	*readline(void);
+static __inline void	 src_free(void);
+
+static __inline u_int	 max(u_int, u_int);
+static u_long		 get_ulong(struct number *);
+
+static __inline void	 push_number(struct number *);
+static __inline void	 push_string(char *);
+static __inline void	 push(struct value *);
+static __inline struct value *tos(void);
+static __inline struct number	*pop_number(void);
+static __inline char	*pop_string(void);
+static __inline void	 clear_stack(void);
+static __inline void	 print_tos(void);
+static void		 pop_print(void);
+static void		 pop_printn(void);
+static __inline void	 print_stack(void);
+static __inline void	 dup(void);
+static void		 swap(void);
+static void		 drop(void);
+
+static void		 get_scale(void);
+static void		 set_scale(void);
+static void		 get_obase(void);
+static void		 set_obase(void);
+static void		 get_ibase(void);
+static void		 set_ibase(void);
+static void		 stackdepth(void);
+static void		 push_scale(void);
+static u_int		 count_digits(const struct number *);
+static void		 num_digits(void);
+static void		 to_ascii(void);
+static void		 push_line(void);
+static void		 comment(void);
+static void		 bexec(char *);
+static void		 badd(void);
+static void		 bsub(void);
+static void		 bmul(void);
+static void		 bdiv(void);
+static void		 bmod(void);
+static void		 bdivmod(void);
+static void		 bexp(void);
+static bool		 bsqrt_stop(const BIGNUM *, const BIGNUM *, u_int *);
+static void		 bsqrt(void);
+static void		 not(void);
+static void		 equal_numbers(void);
+static void		 less_numbers(void);
+static void		 lesseq_numbers(void);
+static void		 equal(void);
+static void		 not_equal(void);
+static void		 less(void);
+static void		 not_less(void);
+static void		 greater(void);
+static void		 not_greater(void);
+static void		 not_compare(void);
+static bool		 compare_numbers(enum bcode_compare, struct number *,
+			     struct number *);
+static void		 compare(enum bcode_compare);
+static int		 readreg(void);
+static void		 load(void);
+static void		 store(void);
+static void		 load_stack(void);
+static void		 store_stack(void);
+static void		 load_array(void);
+static void		 store_array(void);
+static void		 nop(void);
+static void		 quit(void);
+static void		 quitN(void);
+static void		 skipN(void);
+static void		 skip_until_mark(void);
+static void		 parse_number(void);
+static void		 unknown(void);
+static void		 eval_string(char *);
+static void		 eval_line(void);
+static void		 eval_tos(void);
+
+
+typedef void		(*opcode_function)(void);
+
+struct jump_entry {
+	u_char		 ch;
+	opcode_function	 f;
+};
+
+static opcode_function jump_table[UCHAR_MAX];
+
+static const struct jump_entry jump_table_data[] = {
+	{ ' ',	nop		},
+	{ '!',	not_compare	},
+	{ '#',	comment		},
+	{ '%',	bmod		},
+	{ '(',	less_numbers	},
+	{ '*',	bmul		},
+	{ '+',	badd		},
+	{ '-',	bsub		},
+	{ '.',	parse_number	},
+	{ '/',	bdiv		},
+	{ '0',	parse_number	},
+	{ '1',	parse_number	},
+	{ '2',	parse_number	},
+	{ '3',	parse_number	},
+	{ '4',	parse_number	},
+	{ '5',	parse_number	},
+	{ '6',	parse_number	},
+	{ '7',	parse_number	},
+	{ '8',	parse_number	},
+	{ '9',	parse_number	},
+	{ ':',	store_array	},
+	{ ';',	load_array	},
+	{ '<',	less		},
+	{ '=',	equal		},
+	{ '>',	greater		},
+	{ '?',	eval_line	},
+	{ 'A',	parse_number	},
+	{ 'B',	parse_number	},
+	{ 'C',	parse_number	},
+	{ 'D',	parse_number	},
+	{ 'E',	parse_number	},
+	{ 'F',	parse_number	},
+	{ 'G',	equal_numbers	},
+	{ 'I',	get_ibase	},
+	{ 'J',	skipN		},
+	{ 'K',	get_scale	},
+	{ 'L',	load_stack	},
+	{ 'M',	nop		},
+	{ 'N',	not		},
+	{ 'O',	get_obase	},
+	{ 'P',	pop_print	},
+	{ 'Q',	quitN		},
+	{ 'R',	drop		},
+	{ 'S',	store_stack	},
+	{ 'X',	push_scale	},
+	{ 'Z',	num_digits	},
+	{ '[',	push_line	},
+	{ '\f',	nop		},
+	{ '\n',	nop		},
+	{ '\r',	nop		},
+	{ '\t',	nop		},
+	{ '^',	bexp		},
+	{ '_',	parse_number	},
+	{ 'a',	to_ascii	},
+	{ 'c',	clear_stack	},
+	{ 'd',	dup		},
+	{ 'f',	print_stack	},
+	{ 'i',	set_ibase	},
+	{ 'k',	set_scale	},
+	{ 'l',	load		},
+	{ 'n',	pop_printn	},
+	{ 'o',	set_obase	},
+	{ 'p',	print_tos	},
+	{ 'q',	quit		},
+	{ 'r',	swap		},
+	{ 's',	store		},
+	{ 'v',	bsqrt		},
+	{ 'x',	eval_tos	},
+	{ 'z',	stackdepth	},
+	{ '{',	lesseq_numbers	},
+	{ '~',	bdivmod		}
+};
+
+#define JUMP_TABLE_DATA_SIZE \
+	(sizeof(jump_table_data)/sizeof(jump_table_data[0]))
+
+static void
+sighandler(int ignored)
+{
+
+	switch (ignored)
+	{
+	default:
+		bmachine.interrupted = true;
+	}
+}
+
+void
+init_bmachine(bool extended_registers)
+{
+	unsigned int	 i;
+
+	bmachine.extended_regs = extended_registers;
+	bmachine.reg_array_size = bmachine.extended_regs ?
+	    REG_ARRAY_SIZE_BIG : REG_ARRAY_SIZE_SMALL;
+
+	bmachine.reg = calloc(bmachine.reg_array_size,
+	    sizeof(bmachine.reg[0]));
+	if (bmachine.reg == NULL)
+		err(1, NULL);
+
+	for (i = 0; i < UCHAR_MAX; i++)
+		jump_table[i] = unknown;
+	for (i = 0; i < JUMP_TABLE_DATA_SIZE; i++)
+		jump_table[jump_table_data[i].ch] = jump_table_data[i].f;
+
+	stack_init(&bmachine.stack);
+
+	for (i = 0; i < bmachine.reg_array_size; i++)
+		stack_init(&bmachine.reg[i]);
+
+	bmachine.readstack_sz = READSTACK_SIZE;
+	bmachine.readstack = calloc(sizeof(struct source),
+	    bmachine.readstack_sz);
+	if (bmachine.readstack == NULL)
+		err(1, NULL);
+	bmachine.obase = bmachine.ibase = 10;
+	BN_init(&zero);
+	bn_check(BN_zero(&zero));
+	signal(SIGINT, sighandler);
+}
+
+/* Reset the things needed before processing a (new) file */
+void
+reset_bmachine(struct source *src)
+{
+
+	bmachine.readsp = 0;
+	bmachine.readstack[0] = *src;
+}
+
+static __inline int
+readch(void)
+{
+	struct source	*src = &bmachine.readstack[bmachine.readsp];
+
+	return (src->vtable->readchar(src));
+}
+
+static __inline void
+unreadch(void)
+{
+	struct source	*src = &bmachine.readstack[bmachine.readsp];
+
+	src->vtable->unreadchar(src);
+}
+
+static __inline char *
+readline(void)
+{
+	struct source	*src = &bmachine.readstack[bmachine.readsp];
+
+	return (src->vtable->readline(src));
+}
+
+static __inline void
+src_free(void)
+{
+	struct source	*src = &bmachine.readstack[bmachine.readsp];
+
+	src->vtable->free(src);
+}
+
+#ifdef DEBUGGING
+void
+pn(const char *str, const struct number *n)
+{
+	char	*p = BN_bn2dec(n->number);
+
+	if (p == NULL)
+		err(1, "BN_bn2dec failed");
+	fputs(str, stderr);
+	fprintf(stderr, " %s (%u)\n" , p, n->scale);
+	OPENSSL_free(p);
+}
+
+void
+pbn(const char *str, const BIGNUM *n)
+{
+	char	*p = BN_bn2dec(n);
+
+	if (p == NULL)
+		err(1, "BN_bn2dec failed");
+	fputs(str, stderr);
+	fprintf(stderr, " %s\n", p);
+	OPENSSL_free(p);
+}
+
+#endif
+
+static __inline u_int
+max(u_int a, u_int b)
+{
+
+	return (a > b ? a : b);
+}
+
+static unsigned long factors[] = {
+	0, 10, 100, 1000, 10000, 100000, 1000000, 10000000,
+	100000000, 1000000000
+};
+
+void
+scale_number(BIGNUM *n, int s)
+{
+	unsigned int	 abs_scale;
+
+	if (s == 0)
+		return;
+
+	abs_scale = s > 0 ? s : -s;
+
+	if (abs_scale < sizeof(factors)/sizeof(factors[0])) {
+		if (s > 0)
+			bn_check(BN_mul_word(n, factors[abs_scale]));
+		else
+			BN_div_word(n, factors[abs_scale]);
+	} else {
+		BIGNUM	*a, *p;
+		BN_CTX	*ctx;
+
+		a = BN_new();
+		bn_checkp(a);
+		p = BN_new();
+		bn_checkp(p);
+		ctx = BN_CTX_new();
+		bn_checkp(ctx);
+
+		bn_check(BN_set_word(a, 10));
+		bn_check(BN_set_word(p, abs_scale));
+		bn_check(BN_exp(a, a, p, ctx));
+		if (s > 0)
+			bn_check(BN_mul(n, n, a, ctx));
+		else
+			bn_check(BN_div(n, NULL, n, a, ctx));
+		BN_CTX_free(ctx);
+		BN_free(a);
+		BN_free(p);
+	}
+}
+
+void
+split_number(const struct number *n, BIGNUM *i, BIGNUM *f)
+{
+	u_long	 rem;
+
+	bn_checkp(BN_copy(i, n->number));
+
+	if (n->scale == 0 && f != NULL)
+		bn_check(BN_zero(f));
+	else if (n->scale < sizeof(factors)/sizeof(factors[0])) {
+		rem = BN_div_word(i, factors[n->scale]);
+		if (f != NULL)
+			bn_check(BN_set_word(f, rem));
+	} else {
+		BIGNUM	*a, *p;
+		BN_CTX	*ctx;
+
+		a = BN_new();
+		bn_checkp(a);
+		p = BN_new();
+		bn_checkp(p);
+		ctx = BN_CTX_new();
+		bn_checkp(ctx);
+
+		bn_check(BN_set_word(a, 10));
+		bn_check(BN_set_word(p, n->scale));
+		bn_check(BN_exp(a, a, p, ctx));
+		bn_check(BN_div(i, f, n->number, a, ctx));
+		BN_CTX_free(ctx);
+		BN_free(a);
+		BN_free(p);
+	}
+}
+
+__inline void
+normalize(struct number *n, u_int s)
+{
+
+	scale_number(n->number, s - n->scale);
+	n->scale = s;
+}
+
+static u_long
+get_ulong(struct number *n)
+{
+
+	normalize(n, 0);
+	return (BN_get_word(n->number));
+}
+
+void
+negate(struct number *n)
+{
+
+	bn_check(BN_sub(n->number, &zero, n->number));
+}
+
+static __inline void
+push_number(struct number *n)
+{
+
+	stack_pushnumber(&bmachine.stack, n);
+}
+
+static __inline void
+push_string(char *string)
+{
+
+	stack_pushstring(&bmachine.stack, string);
+}
+
+static __inline void
+push(struct value *v)
+{
+
+	stack_push(&bmachine.stack, v);
+}
+
+static __inline struct value *
+tos(void)
+{
+
+	return (stack_tos(&bmachine.stack));
+}
+
+static __inline struct value *
+pop(void)
+{
+
+	return (stack_pop(&bmachine.stack));
+}
+
+static __inline struct number *
+pop_number(void)
+{
+
+	return (stack_popnumber(&bmachine.stack));
+}
+
+static __inline char *
+pop_string(void)
+{
+
+	return (stack_popstring(&bmachine.stack));
+}
+
+static __inline void
+clear_stack(void)
+{
+
+	stack_clear(&bmachine.stack);
+}
+
+static __inline void
+print_stack(void)
+{
+
+	stack_print(stdout, &bmachine.stack, "", bmachine.obase);
+}
+
+static __inline void
+print_tos(void)
+{
+	struct value	*value = tos();
+
+	if (value != NULL) {
+		print_value(stdout, value, "", bmachine.obase);
+		putchar('\n');
+	}
+	else
+		warnx("stack empty");
+}
+
+static void
+pop_print(void)
+{
+	struct value	*value = pop();
+
+	if (value != NULL) {
+		switch (value->type) {
+		case BCODE_NONE:
+			break;
+		case BCODE_NUMBER:
+			normalize(value->u.num, 0);
+			print_ascii(stdout, value->u.num);
+			fflush(stdout);
+			break;
+		case BCODE_STRING:
+			fputs(value->u.string, stdout);
+			fflush(stdout);
+			break;
+		}
+		stack_free_value(value);
+	}
+}
+
+static void
+pop_printn(void)
+{
+	struct value	*value = pop();
+
+	if (value != NULL) {
+		print_value(stdout, value, "", bmachine.obase);
+		fflush(stdout);
+		stack_free_value(value);
+	}
+}
+
+static __inline void
+dup(void)
+{
+
+	stack_dup(&bmachine.stack);
+}
+
+static void
+swap(void)
+{
+
+	stack_swap(&bmachine.stack);
+}
+
+static void
+drop(void)
+{
+	struct value	*v = pop();
+	if (v != NULL)
+		stack_free_value(v);
+}
+
+static void
+get_scale(void)
+{
+	struct number	*n;
+
+	n = new_number();
+	bn_check(BN_set_word(n->number, bmachine.scale));
+	push_number(n);
+}
+
+static void
+set_scale(void)
+{
+	struct number	*n;
+	u_long		 scale;
+
+	n = pop_number();
+	if (n != NULL) {
+		if (BN_cmp(n->number, &zero) < 0)
+			warnx("scale must be a nonnegative number");
+		else {
+			scale = get_ulong(n);
+			if (scale != BN_MASK2 && scale <= UINT_MAX)
+				bmachine.scale = (u_int)scale;
+			else
+				warnx("scale too large");
+			}
+		free_number(n);
+	}
+}
+
+static void
+get_obase(void)
+{
+	struct number	*n;
+
+	n = new_number();
+	bn_check(BN_set_word(n->number, bmachine.obase));
+	push_number(n);
+}
+
+static void
+set_obase(void)
+{
+	struct number	*n;
+	u_long		 base;
+
+	n = pop_number();
+	if (n != NULL) {
+		base = get_ulong(n);
+		if (base != BN_MASK2 && base > 1 && base <= UINT_MAX)
+			bmachine.obase = (u_int)base;
+		else
+			warnx("output base must be a number greater than 1");
+		free_number(n);
+	}
+}
+
+static void
+get_ibase(void)
+{
+	struct number	*n;
+
+	n = new_number();
+	bn_check(BN_set_word(n->number, bmachine.ibase));
+	push_number(n);
+}
+
+static void
+set_ibase(void)
+{
+	struct number	*n;
+	u_long		 base;
+
+	n = pop_number();
+	if (n != NULL) {
+		base = get_ulong(n);
+		if (base != BN_MASK2 && 2 <= base && base <= 16)
+			bmachine.ibase = (u_int)base;
+		else
+			warnx("input base must be a number between 2 and 16 "
+			    "(inclusive)");
+		free_number(n);
+	}
+}
+
+static void
+stackdepth(void)
+{
+	size_t		 i;
+	struct number	*n;
+
+	i = stack_size(&bmachine.stack);
+	n = new_number();
+	bn_check(BN_set_word(n->number, i));
+	push_number(n);
+}
+
+static void
+push_scale(void)
+{
+	struct value	*value;
+	u_int		 scale = 0;
+	struct number	*n;
+
+
+	value = pop();
+	if (value != NULL) {
+		switch (value->type) {
+		case BCODE_NONE:
+			return;
+		case BCODE_NUMBER:
+			scale = value->u.num->scale;
+			break;
+		case BCODE_STRING:
+			break;
+		}
+		stack_free_value(value);
+		n = new_number();
+		bn_check(BN_set_word(n->number, scale));
+		push_number(n);
+	}
+}
+
+static u_int
+count_digits(const struct number *n)
+{
+	struct number	*int_part, *fract_part;
+	u_int		 i;
+
+	if (BN_is_zero(n->number))
+		return (1);
+
+	int_part = new_number();
+	fract_part = new_number();
+	fract_part->scale = n->scale;
+	split_number(n, int_part->number, fract_part->number);
+
+	i = 0;
+	while (!BN_is_zero(int_part->number)) {
+		BN_div_word(int_part->number, 10);
+		i++;
+	}
+	free_number(int_part);
+	free_number(fract_part);
+	return (i + n->scale);
+}
+
+static void
+num_digits(void)
+{
+	struct value	*value;
+	size_t		 digits;
+	struct number	*n = NULL;
+
+	value = pop();
+	if (value != NULL) {
+		switch (value->type) {
+		case BCODE_NONE:
+			return;
+		case BCODE_NUMBER:
+			digits = count_digits(value->u.num);
+			n = new_number();
+			bn_check(BN_set_word(n->number, digits));
+			break;
+		case BCODE_STRING:
+			digits = strlen(value->u.string);
+			n = new_number();
+			bn_check(BN_set_word(n->number, digits));
+			break;
+		}
+		stack_free_value(value);
+		push_number(n);
+	}
+}
+
+static void
+to_ascii(void)
+{
+	char		 str[2];
+	struct value	*value;
+	struct number	*n;
+
+	value = pop();
+	if (value != NULL) {
+		str[1] = '\0';
+		switch (value->type) {
+		case BCODE_NONE:
+			return;
+		case BCODE_NUMBER:
+			n = value->u.num;
+			normalize(n, 0);
+			if (BN_num_bits(n->number) > 8)
+				bn_check(BN_mask_bits(n->number, 8));
+			str[0] = (char)BN_get_word(n->number);
+			break;
+		case BCODE_STRING:
+			str[0] = value->u.string[0];
+			break;
+		}
+		stack_free_value(value);
+		push_string(bstrdup(str));
+	}
+}
+
+static int
+readreg(void)
+{
+	int	 idx, ch1, ch2;
+
+	idx = readch();
+	if (idx == 0xff && bmachine.extended_regs) {
+		ch1 = readch();
+		ch2 = readch();
+		if (ch1 == EOF || ch2 == EOF) {
+			warnx("unexpected eof");
+			idx = -1;
+		} else
+			idx = (ch1 << 8) + ch2 + UCHAR_MAX + 1;
+	}
+	if (idx < 0 || (unsigned)idx >= bmachine.reg_array_size) {
+		warnx("internal error: reg num = %d", idx);
+		idx = -1;
+	}
+	return (idx);
+}
+
+static void
+load(void)
+{
+	int		 idx;
+	struct value	*v, copy;
+	struct number	*n;
+
+	idx = readreg();
+	if (idx >= 0) {
+		v = stack_tos(&bmachine.reg[idx]);
+		if (v == NULL) {
+			n = new_number();
+			bn_check(BN_zero(n->number));
+			push_number(n);
+		} else
+			push(stack_dup_value(v, &copy));
+	}
+}
+
+static void
+store(void)
+{
+	int		 idx;
+	struct value	*val;
+
+	idx = readreg();
+	if (idx >= 0) {
+		val = pop();
+		if (val == NULL) {
+			return;
+		}
+		stack_set_tos(&bmachine.reg[idx], val);
+	}
+}
+
+static void
+load_stack(void)
+{
+	int		 idx;
+	struct stack	*stack;
+	struct value	*value;
+
+	idx = readreg();
+	if (idx >= 0) {
+		stack = &bmachine.reg[idx];
+		value = NULL;
+		if (stack_size(stack) > 0) {
+			value = stack_pop(stack);
+		}
+		if (value != NULL)
+			push(value);
+		else
+			warnx("stack register '%c' (0%o) is empty",
+			    idx, idx);
+	}
+}
+
+static void
+store_stack(void)
+{
+	int		 idx;
+	struct value	*value;
+
+	idx = readreg();
+	if (idx >= 0) {
+		value = pop();
+		if (value == NULL)
+			return;
+		stack_push(&bmachine.reg[idx], value);
+	}
+}
+
+static void
+load_array(void)
+{
+	int			 reg;
+	struct number		*inumber, *n;
+	u_long			 idx;
+	struct stack		*stack;
+	struct value		*v, copy;
+
+	reg = readreg();
+	if (reg >= 0) {
+		inumber = pop_number();
+		if (inumber == NULL)
+			return;
+		idx = get_ulong(inumber);
+		if (BN_cmp(inumber->number, &zero) < 0)
+			warnx("negative idx");
+		else if (idx == BN_MASK2 || idx > MAX_ARRAY_INDEX)
+			warnx("idx too big");
+		else {
+			stack = &bmachine.reg[reg];
+			v = frame_retrieve(stack, idx);
+			if (v == NULL || v->type == BCODE_NONE) {
+				n = new_number();
+				bn_check(BN_zero(n->number));
+				push_number(n);
+			}
+			else
+				push(stack_dup_value(v, &copy));
+		}
+		free_number(inumber);
+	}
+}
+
+static void
+store_array(void)
+{
+	int			 reg;
+	struct number		*inumber;
+	u_long			 idx;
+	struct value		*value;
+	struct stack		*stack;
+
+	reg = readreg();
+	if (reg >= 0) {
+		inumber = pop_number();
+		if (inumber == NULL)
+			return;
+		value = pop();
+		if (value == NULL) {
+			free_number(inumber);
+			return;
+		}
+		idx = get_ulong(inumber);
+		if (BN_cmp(inumber->number, &zero) < 0) {
+			warnx("negative idx");
+			stack_free_value(value);
+		} else if (idx == BN_MASK2 || idx > MAX_ARRAY_INDEX) {
+			warnx("idx too big");
+			stack_free_value(value);
+		} else {
+			stack = &bmachine.reg[reg];
+			frame_assign(stack, idx, value);
+		}
+		free_number(inumber);
+	}
+}
+
+static void
+push_line(void)
+{
+
+	push_string(read_string(&bmachine.readstack[bmachine.readsp]));
+}
+
+static void
+comment(void)
+{
+
+	free(readline());
+}
+
+static void
+bexec(char *line)
+{
+
+	system(line);
+	free(line);
+}
+
+static void
+badd(void)
+{
+	struct number	*a, *b;
+	struct number	*r;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+
+	r = new_number();
+	r->scale = max(a->scale, b->scale);
+	if (r->scale > a->scale)
+		normalize(a, r->scale);
+	else if (r->scale > b->scale)
+		normalize(b, r->scale);
+	bn_check(BN_add(r->number, a->number, b->number));
+	push_number(r);
+	free_number(a);
+	free_number(b);
+}
+
+static void
+bsub(void)
+{
+	struct number	*a, *b;
+	struct number	*r;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+
+	r = new_number();
+
+	r->scale = max(a->scale, b->scale);
+	if (r->scale > a->scale)
+		normalize(a, r->scale);
+	else if (r->scale > b->scale)
+		normalize(b, r->scale);
+	bn_check(BN_sub(r->number, b->number, a->number));
+	push_number(r);
+	free_number(a);
+	free_number(b);
+}
+
+void
+bmul_number(struct number *r, struct number *a, struct number *b)
+{
+	BN_CTX		*ctx;
+
+	/* Create copies of the scales, since r might be equal to a or b */
+	u_int ascale = a->scale;
+	u_int bscale = b->scale;
+	u_int rscale = ascale + bscale;
+
+	ctx = BN_CTX_new();
+	bn_checkp(ctx);
+	bn_check(BN_mul(r->number, a->number, b->number, ctx));
+	BN_CTX_free(ctx);
+
+	if (rscale > bmachine.scale && rscale > ascale && rscale > bscale) {
+		r->scale = rscale;
+		normalize(r, max(bmachine.scale, max(ascale, bscale)));
+	} else
+		r->scale = rscale;
+}
+
+static void
+bmul(void)
+{
+	struct number	*a, *b;
+	struct number	*r;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+
+	r = new_number();
+	bmul_number(r, a, b);
+
+	push_number(r);
+	free_number(a);
+	free_number(b);
+}
+
+static void
+bdiv(void)
+{
+	struct number	*a, *b;
+	struct number	*r;
+	u_int		 scale;
+	BN_CTX		*ctx;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+
+	r = new_number();
+	r->scale = bmachine.scale;
+	scale = max(a->scale, b->scale);
+
+	if (BN_is_zero(a->number))
+		warnx("divide by zero");
+	else {
+		normalize(a, scale);
+		normalize(b, scale + r->scale);
+
+		ctx = BN_CTX_new();
+		bn_checkp(ctx);
+		bn_check(BN_div(r->number, NULL, b->number, a->number, ctx));
+		BN_CTX_free(ctx);
+	}
+	push_number(r);
+	free_number(a);
+	free_number(b);
+}
+
+static void
+bmod(void)
+{
+	struct number	*a, *b;
+	struct number	*r;
+	u_int		 scale;
+	BN_CTX		*ctx;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+
+	r = new_number();
+	scale = max(a->scale, b->scale);
+	r->scale = max(b->scale, a->scale + bmachine.scale);
+
+	if (BN_is_zero(a->number))
+		warnx("remainder by zero");
+	else {
+		normalize(a, scale);
+		normalize(b, scale + bmachine.scale);
+
+		ctx = BN_CTX_new();
+		bn_checkp(ctx);
+		bn_check(BN_mod(r->number, b->number, a->number, ctx));
+		BN_CTX_free(ctx);
+	}
+	push_number(r);
+	free_number(a);
+	free_number(b);
+}
+
+static void
+bdivmod(void)
+{
+	struct number	*a, *b;
+	struct number	*rdiv, *rmod;
+	u_int		 scale;
+	BN_CTX		*ctx;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+
+	rdiv = new_number();
+	rmod = new_number();
+	rdiv->scale = bmachine.scale;
+	rmod->scale = max(b->scale, a->scale + bmachine.scale);
+	scale = max(a->scale, b->scale);
+
+	if (BN_is_zero(a->number))
+		warnx("divide by zero");
+	else {
+		normalize(a, scale);
+		normalize(b, scale + bmachine.scale);
+
+		ctx = BN_CTX_new();
+		bn_checkp(ctx);
+		bn_check(BN_div(rdiv->number, rmod->number,
+		    b->number, a->number, ctx));
+		BN_CTX_free(ctx);
+	}
+	push_number(rdiv);
+	push_number(rmod);
+	free_number(a);
+	free_number(b);
+}
+
+static void
+bexp(void)
+{
+	struct number	*a, *p;
+	struct number	*r;
+	bool		 neg;
+	u_int		 scale;
+
+	p = pop_number();
+	if (p == NULL) {
+		return;
+	}
+	a = pop_number();
+	if (a == NULL) {
+		push_number(p);
+		return;
+	}
+
+	if (p->scale != 0)
+		warnx("Runtime warning: non-zero scale in exponent");
+	normalize(p, 0);
+
+	neg = false;
+	if (BN_cmp(p->number, &zero) < 0) {
+		neg = true;
+		negate(p);
+		scale = bmachine.scale;
+	} else {
+		/* Posix bc says min(a.scale * b, max(a.scale, scale) */
+		u_long	 b;
+		u_int	 m;
+
+		b = BN_get_word(p->number);
+		m = max(a->scale, bmachine.scale);
+		scale = a->scale * (u_int)b;
+		if (scale > m || (a->scale > 0 && (b == BN_MASK2 ||
+		    b > UINT_MAX)))
+			scale = m;
+	}
+
+	if (BN_is_zero(p->number)) {
+		r = new_number();
+		bn_check(BN_one(r->number));
+		normalize(r, scale);
+	} else {
+		while (!BN_is_bit_set(p->number, 0)) {
+			bmul_number(a, a, a);
+			bn_check(BN_rshift1(p->number, p->number));
+		}
+
+		r = dup_number(a);
+		normalize(r, scale);
+		bn_check(BN_rshift1(p->number, p->number));
+
+		while (!BN_is_zero(p->number)) {
+			bmul_number(a, a, a);
+			if (BN_is_bit_set(p->number, 0))
+				bmul_number(r, r, a);
+			bn_check(BN_rshift1(p->number, p->number));
+		}
+
+		if (neg) {
+			BN_CTX	*ctx;
+			BIGNUM	*one;
+
+			one = BN_new();
+			bn_checkp(one);
+			bn_check(BN_one(one));
+			ctx = BN_CTX_new();
+			bn_checkp(ctx);
+			scale_number(one, r->scale + scale);
+			normalize(r, scale);
+			bn_check(BN_div(r->number, NULL, one, r->number, ctx));
+			BN_free(one);
+			BN_CTX_free(ctx);
+		} else
+			normalize(r, scale);
+	}
+	push_number(r);
+	free_number(a);
+	free_number(p);
+}
+
+static bool
+bsqrt_stop(const BIGNUM *x, const BIGNUM *y, u_int *onecount)
+{
+	BIGNUM	*r;
+	bool	 ret;
+
+	r = BN_new();
+	bn_checkp(r);
+	bn_check(BN_sub(r, x, y));
+	if (BN_is_one(r))
+		(*onecount)++;
+	ret = BN_is_zero(r);
+	BN_free(r);
+	return (ret || *onecount > 1);
+}
+
+static void
+bsqrt(void)
+{
+	struct number	*n;
+	struct number	*r;
+	BIGNUM		*x, *y;
+	u_int		 scale, onecount;
+	BN_CTX		*ctx;
+
+	onecount = 0;
+	n = pop_number();
+	if (n == NULL) {
+		return;
+	}
+	if (BN_is_zero(n->number)) {
+		r = new_number();
+		push_number(r);
+	} else if (BN_cmp(n->number, &zero) < 0)
+		warnx("square root of negative number");
+	else {
+		scale = max(bmachine.scale, n->scale);
+		normalize(n, 2*scale);
+		x = BN_dup(n->number);
+		bn_checkp(x);
+		bn_check(BN_rshift(x, x, BN_num_bits(x)/2));
+		y = BN_new();
+		bn_checkp(y);
+		ctx = BN_CTX_new();
+		bn_checkp(ctx);
+		for (;;) {
+			bn_checkp(BN_copy(y, x));
+			bn_check(BN_div(x, NULL, n->number, x, ctx));
+			bn_check(BN_add(x, x, y));
+			bn_check(BN_rshift1(x, x));
+			if (bsqrt_stop(x, y, &onecount))
+				break;
+		}
+		r = bmalloc(sizeof(*r));
+		r->scale = scale;
+		r->number = y;
+		BN_free(x);
+		BN_CTX_free(ctx);
+		push_number(r);
+	}
+
+	free_number(n);
+}
+
+static void
+not(void)
+{
+	struct number	*a;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	a->scale = 0;
+	bn_check(BN_set_word(a->number, BN_get_word(a->number) ? 0 : 1));
+	push_number(a);
+}
+
+static void
+equal(void)
+{
+
+	compare(BCODE_EQUAL);
+}
+
+static void
+equal_numbers(void)
+{
+	struct number	*a, *b, *r;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+	r = new_number();
+	bn_check(BN_set_word(r->number,
+	    compare_numbers(BCODE_EQUAL, a, b) ? 1 : 0));
+	push_number(r);
+}
+
+static void
+less_numbers(void)
+{
+	struct number	*a, *b, *r;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+	r = new_number();
+	bn_check(BN_set_word(r->number,
+	    compare_numbers(BCODE_LESS, a, b) ? 1 : 0));
+	push_number(r);
+}
+
+static void
+lesseq_numbers(void)
+{
+	struct number	*a, *b, *r;
+
+	a = pop_number();
+	if (a == NULL) {
+		return;
+	}
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+	r = new_number();
+	bn_check(BN_set_word(r->number,
+	    compare_numbers(BCODE_NOT_GREATER, a, b) ? 1 : 0));
+	push_number(r);
+}
+
+static void
+not_equal(void)
+{
+
+	compare(BCODE_NOT_EQUAL);
+}
+
+static void
+less(void)
+{
+
+	compare(BCODE_LESS);
+}
+
+static void
+not_compare(void)
+{
+	switch (readch()) {
+	case '<':
+		not_less();
+		break;
+	case '>':
+		not_greater();
+		break;
+	case '=':
+		not_equal();
+		break;
+	default:
+		unreadch();
+		bexec(readline());
+		break;
+	}
+}
+
+static void
+not_less(void)
+{
+
+	compare(BCODE_NOT_LESS);
+}
+
+static void
+greater(void)
+{
+
+	compare(BCODE_GREATER);
+}
+
+static void
+not_greater(void)
+{
+
+	compare(BCODE_NOT_GREATER);
+}
+
+static bool
+compare_numbers(enum bcode_compare type, struct number *a, struct number *b)
+{
+	u_int	 scale;
+	int	 cmp;
+
+	scale = max(a->scale, b->scale);
+
+	if (scale > a->scale)
+		normalize(a, scale);
+	else if (scale > b->scale)
+		normalize(b, scale);
+
+	cmp = BN_cmp(a->number, b->number);
+
+	free_number(a);
+	free_number(b);
+
+	switch (type) {
+	case BCODE_EQUAL:
+		return (cmp == 0);
+	case BCODE_NOT_EQUAL:
+		return (cmp != 0);
+	case BCODE_LESS:
+		return (cmp < 0);
+	case BCODE_NOT_LESS:
+		return (cmp >= 0);
+	case BCODE_GREATER:
+		return (cmp > 0);
+	case BCODE_NOT_GREATER:
+		return (cmp <= 0);
+	}
+	return (false);
+}
+
+static void
+compare(enum bcode_compare type)
+{
+	int		 idx, elseidx;
+	struct number	*a, *b;
+	bool		 ok;
+	struct value	*v;
+
+	elseidx = NO_ELSE;
+	idx = readreg();
+	if (readch() == 'e')
+		elseidx = readreg();
+	else
+		unreadch();
+
+	a = pop_number();
+	if (a == NULL)
+		return;
+	b = pop_number();
+	if (b == NULL) {
+		push_number(a);
+		return;
+	}
+
+	ok = compare_numbers(type, a, b);
+
+	if (!ok && elseidx != NO_ELSE)
+		idx = elseidx;
+
+	if (idx >= 0 && (ok || (!ok && elseidx != NO_ELSE))) {
+		v = stack_tos(&bmachine.reg[idx]);
+		if (v == NULL)
+			warnx("register '%c' (0%o) is empty", idx, idx);
+		else {
+			switch(v->type) {
+			case BCODE_NONE:
+				warnx("register '%c' (0%o) is empty", idx, idx);
+				break;
+			case BCODE_NUMBER:
+				warn("eval called with non-string argument");
+				break;
+			case BCODE_STRING:
+				eval_string(bstrdup(v->u.string));
+				break;
+			}
+		}
+	}
+}
+
+
+static void
+nop(void)
+{
+}
+
+static void
+quit(void)
+{
+	if (bmachine.readsp < 2)
+		exit(0);
+	src_free();
+	bmachine.readsp--;
+	src_free();
+	bmachine.readsp--;
+}
+
+static void
+quitN(void)
+{
+	struct number	*n;
+	u_long		 i;
+
+	n = pop_number();
+	if (n == NULL)
+		return;
+	i = get_ulong(n);
+	free_number(n);
+	if (i == BN_MASK2 || i == 0)
+		warnx("Q command requires a number >= 1");
+	else if (bmachine.readsp < i)
+		warnx("Q command argument exceeded string execution depth");
+	else {
+		while (i-- > 0) {
+			src_free();
+			bmachine.readsp--;
+		}
+	}
+}
+
+static void
+skipN(void)
+{
+	struct number	*n;
+	u_long		 i;
+
+	n = pop_number();
+	if (n == NULL)
+		return;
+	i = get_ulong(n);
+	if (i == BN_MASK2)
+		warnx("J command requires a number >= 0");
+	else if (i > 0 && bmachine.readsp < i)
+		warnx("J command argument exceeded string execution depth");
+	else {
+		while (i-- > 0) {
+			src_free();
+			bmachine.readsp--;
+		}
+		skip_until_mark();
+	}
+}
+
+static void
+skip_until_mark(void)
+{
+	int	 ch;
+
+	for (;;) {
+		ch = readch();
+		switch (ch) {
+		case 'M':
+			return;
+		case EOF:
+			errx(1, "mark not found");
+			return;
+		case 'l':
+		case 'L':
+		case 's':
+		case 'S':
+		case ':':
+		case ';':
+		case '<':
+		case '>':
+		case '=':
+			readreg();
+			if (readch() == 'e')
+				readreg();
+			else
+				unreadch();
+			break;
+		case '[':
+			free(read_string(&bmachine.readstack[bmachine.readsp]));
+			break;
+		case '!':
+			switch (ch = readch()) {
+				case '<':
+				case '>':
+				case '=':
+					readreg();
+					if (readch() == 'e')
+						readreg();
+					else
+						unreadch();
+					break;
+				default:
+					free(readline());
+					break;
+			}
+			break;
+		default:
+			break;
+		}
+	}
+}
+
+static void
+parse_number(void)
+{
+
+	unreadch();
+	push_number(readnumber(&bmachine.readstack[bmachine.readsp],
+	    bmachine.ibase));
+}
+
+static void
+unknown(void)
+{
+	int ch = bmachine.readstack[bmachine.readsp].lastchar;
+	warnx("%c (0%o) is unimplemented", ch, ch);
+}
+
+static void
+eval_string(char *p)
+{
+	int	 ch;
+
+	if (bmachine.readsp > 0) {
+		/* Check for tail call. Do not recurse in that case. */
+		ch = readch();
+		if (ch == EOF) {
+			src_free();
+			src_setstring(&bmachine.readstack[bmachine.readsp], p);
+			return;
+		} else
+			unreadch();
+	}
+	if (bmachine.readsp == bmachine.readstack_sz - 1) {
+		size_t newsz = bmachine.readstack_sz * 2;
+		struct source *stack;
+		stack = realloc(bmachine.readstack, newsz *
+		    sizeof(struct source));
+		if (stack == NULL)
+			err(1, "recursion too deep");
+		bmachine.readstack_sz = newsz;
+		bmachine.readstack = stack;
+	}
+	src_setstring(&bmachine.readstack[++bmachine.readsp], p);
+}
+
+static void
+eval_line(void)
+{
+	/* Always read from stdin */
+	struct source	 in;
+	char		*p;
+
+	clearerr(stdin);
+	src_setstream(&in, stdin);
+	p = (*in.vtable->readline)(&in);
+	eval_string(p);
+}
+
+static void
+eval_tos(void)
+{
+	char	*p;
+
+	p = pop_string();
+	if (p == NULL)
+		return;
+	eval_string(p);
+}
+
+void
+eval(void)
+{
+	int	 ch;
+
+	for (;;) {
+		ch = readch();
+		if (ch == EOF) {
+			if (bmachine.readsp == 0)
+				return;
+			src_free();
+			bmachine.readsp--;
+			continue;
+		}
+		if (bmachine.interrupted) {
+			if (bmachine.readsp > 0) {
+				src_free();
+				bmachine.readsp--;
+				continue;
+			} else
+				bmachine.interrupted = false;
+		}
+#ifdef DEBUGGING
+		fprintf(stderr, "# %c\n", ch);
+		stack_print(stderr, &bmachine.stack, "* ",
+		    bmachine.obase);
+		fprintf(stderr, "%zd =>\n", bmachine.readsp);
+#endif
+
+		if (0 <= ch && ch < (signed)UCHAR_MAX)
+			(*jump_table[ch])();
+		else
+			warnx("internal error: opcode %d", ch);
+
+#ifdef DEBUGGING
+		stack_print(stderr, &bmachine.stack, "* ",
+		    bmachine.obase);
+		fprintf(stderr, "%zd ==\n", bmachine.readsp);
+#endif
+	}
+}
diff --git a/usr.bin/dc/bcode.h b/usr.bin/dc/bcode.h
new file mode 100644
index 0000000..df175fe
--- /dev/null
+++ b/usr.bin/dc/bcode.h
@@ -0,0 +1,98 @@
+/*	$FreeBSD$						*/
+/*	$OpenBSD: bcode.h,v 1.5 2006/01/16 08:09:25 otto Exp $	*/
+
+/*
+ * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <openssl/bn.h>
+
+struct number {
+	BIGNUM	*number;
+	u_int	 scale;
+};
+
+enum stacktype {
+	BCODE_NONE,
+	BCODE_NUMBER,
+	BCODE_STRING
+};
+
+enum bcode_compare {
+	BCODE_EQUAL,
+	BCODE_NOT_EQUAL,
+	BCODE_LESS,
+	BCODE_NOT_LESS,
+	BCODE_GREATER,
+	BCODE_NOT_GREATER
+};
+
+struct array;
+
+struct value {
+	union {
+		struct number	*num;
+		char		*string;
+	} u;
+	struct array	*array;
+	enum stacktype	 type;
+};
+
+struct array {
+	struct value	*data;
+	size_t		 size;
+};
+
+struct stack {
+	struct value	*stack;
+	ssize_t		 sp;
+	ssize_t		 size;
+};
+
+struct source;
+
+struct vtable {
+	int	(*readchar)(struct source *);
+	void	(*unreadchar)(struct source *);
+	char	*(*readline)(struct source *);
+	void	(*free)(struct source *);
+};
+
+struct source {
+	struct vtable	*vtable;
+	union {
+			FILE	*stream;
+			struct {
+				u_char	*buf;
+				size_t	 pos;
+			} string;
+	} u;
+	int		 lastchar;
+};
+
+void			 init_bmachine(bool);
+void			 reset_bmachine(struct source *);
+void			 scale_number(BIGNUM *, int);
+void			 normalize(struct number *, u_int);
+void			 eval(void);
+void			 pn(const char *, const struct number *);
+void			 pbn(const char *, const BIGNUM *);
+void			 negate(struct number *);
+void			 split_number(const struct number *, BIGNUM *, BIGNUM *);
+void			 bmul_number(struct number *, struct number *,
+			    struct number *);
+
+extern BIGNUM		 zero;
diff --git a/usr.bin/dc/dc.1 b/usr.bin/dc/dc.1
new file mode 100644
index 0000000..1706538
--- /dev/null
+++ b/usr.bin/dc/dc.1
@@ -0,0 +1,552 @@
+.\"	$FreeBSD$
+.\"	$OpenBSD: dc.1,v 1.24 2010/01/02 19:48:56 schwarze Exp $
+.\"
+.\" Copyright (C) Caldera International Inc.  2001-2002.
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code and documentation must retain the above
+.\"    copyright notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed or owned by Caldera
+.\"	International, Inc.
+.\" 4. Neither the name of Caldera International, Inc. nor the names of other
+.\"    contributors may be used to endorse or promote products derived from
+.\"    this software without specific prior written permission.
+.\"
+.\" USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
+.\" INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT,
+.\" INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+.\" POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\"	@(#)dc.1	8.1 (Berkeley) 6/6/93
+.\"
+.Dd Jan 28 2009
+.Dt DC 1
+.Os
+.Sh NAME
+.Nm dc
+.Nd desk calculator
+.Sh SYNOPSIS
+.Nm
+.Op Fl hxV
+.Op Fl e Ar expression
+.Op Fl f Ar filename
+.Op Ar filename
+.Sh DESCRIPTION
+.Nm
+is an arbitrary precision arithmetic package.
+The overall structure of
+.Nm
+is
+a stacking (reverse Polish) calculator i.e.\&
+numbers are stored on a stack.
+Adding a number pushes it onto the stack.
+Arithmetic operations pop arguments off the stack
+and push the results.
+See also the
+.Xr bc 1
+utility, which is a preprocessor for
+.Nm
+providing infix notation and a C-like syntax
+which implements functions and reasonable control
+structures for programs.
+The options are as follows:
+.Bl -tag -width Ds
+.It Fl e Ar expr
+.It Fl Fl expression Ar expr
+Evaluate
+.Ar expression .
+If multiple
+.Fl e
+options are specified, they will be processed in the order given.
+If no
+.Ar filename
+argument is given, execution will stop after processing the expressions
+given on the command line,
+otherwise processing will continue with the contents of
+.Ar filename .
+.It Fl f Ar filename
+.It Fl Fl file Ar filename
+Process the content of the given file before further calculations are done.
+If multiple
+.Fl f
+options are specified, they will be processed in the order given.
+.It Fl h
+.It Fl Fl help
+Print short usage info.
+.It Fl V
+.It Fl Fl version
+Print version info.
+.It Fl x
+Enable extended register mode.
+This mode is used by
+.Xr bc 1
+to allow more than 256 registers.
+See
+.Sx Registers
+for a more detailed description.
+.El
+.Pp
+Ordinarily,
+.Nm
+operates on decimal integers,
+but one may specify an input base, output base,
+and a number of fractional digits (scale) to be maintained.
+If an argument is given,
+input is taken from that file until its end,
+then from the standard input.
+Whitespace is ignored, except where it signals the end of a number,
+end of a line or when a register name is expected.
+The following constructions are recognized:
+.Bl -tag -width "number"
+.It Va number
+The value of the number is pushed on the stack.
+A number is an unbroken string of the digits 0\-9 and letters A\-F.
+It may be preceded by an underscore
+.Pq Sq _
+to input a negative number.
+A number may contain a single decimal point.
+A number may also contain the characters A\-F, with the values 10\-15.
+.It Cm "+ - / * % ~ ^"
+The
+top two values on the stack are added
+(+),
+subtracted
+(\-),
+multiplied (*),
+divided (/),
+remaindered (%),
+divided and remaindered (~),
+or exponentiated (^).
+The two entries are popped off the stack;
+the result is pushed on the stack in their place.
+Any fractional part of an exponent is ignored.
+.Pp
+For addition and subtraction, the scale of the result is the maximum
+of scales of the operands.
+For division the scale of the result is defined
+by the scale set by the
+.Ic k
+operation.
+For multiplication, the scale is defined by the expression
+.Sy min(a+b,max(a,b,scale)) ,
+where
+.Sy a
+and
+.Sy b
+are the scales of the operands, and
+.Sy scale
+is the scale defined by the
+.Ic k
+operation.
+For exponentiation with a non-negative exponent, the scale of the result is
+.Sy min(a*b,max(scale,a)) ,
+where
+.Sy a
+is the scale of the base, and
+.Sy b
+is the
+.Em value
+of the exponent.
+If the exponent is negative, the scale of the result is the scale
+defined by the
+.Ic k
+operation.
+.Pp
+In the case of the division and modulus operator (~),
+the resultant quotient is pushed first followed by the remainder.
+This is a shorthand for the sequence:
+.Bd -literal -offset indent -compact
+x y / x y %
+.Ed
+The division and modulus operator is a non-portable extension.
+.It Ic a
+Pop the top value from the stack.
+If that value is a number, compute the integer part of the number modulo 256.
+If the result is zero, push an empty string.
+Otherwise push a one character string by interpreting the computed value
+as an
+.Tn ASCII
+character.
+.Pp
+If the top value is a string, push a string containing the first character
+of the original string.
+If the original string is empty, an empty string is pushed back.
+The
+.Ic a
+operator is a non-portable extension.
+.It Ic c
+All values on the stack are popped.
+.It Ic d
+The top value on the stack is duplicated.
+.It Ic f
+All values on the stack are printed, separated by newlines.
+.It Ic G
+The top two numbers are popped from the stack and compared.
+A one is pushed if the top of the stack is equal to the second number
+on the stack.
+A zero is pushed otherwise.
+This is a non-portable extension.
+.It Ic I
+Pushes the input base on the top of the stack.
+.It Ic i
+The top value on the stack is popped and used as the
+base for further input.
+The initial input base is 10.
+.It Ic J
+Pop the top value from the stack.
+The recursion level is popped by that value and, following that,
+the input is skipped until the first occurrence of the
+.Ic M
+operator.
+The
+.Ic J
+operator is a non-portable extension, used by the
+.Xr bc 1
+command.
+.It Ic K
+The current scale factor is pushed onto the stack.
+.It Ic k
+The top of the stack is popped, and that value is used as
+a non-negative scale factor:
+the appropriate number of places
+are printed on output,
+and maintained during multiplication, division, and exponentiation.
+The interaction of scale factor,
+input base, and output base will be reasonable if all are changed
+together.
+.It Ic L Ns Ar x
+Register
+.Ar x
+is treated as a stack and its top value is popped onto the main stack.
+.It Ic l Ns Ar x
+The
+value in register
+.Ar x
+is pushed on the stack.
+The register
+.Ar x
+is not altered.
+Initially, all registers contain the value zero.
+.It Ic M
+Mark used by the
+.Ic J
+operator.
+The
+.Ic M
+operator is a non-portable extensions, used by the
+.Xr bc 1
+command.
+.It Ic N
+The top of the stack is replaced by one if the top of the stack
+is equal to zero.
+If the top of the stack is unequal to zero, it is replaced by zero.
+This is a non-portable extension.
+.It Ic n
+The top value on the stack is popped and printed without a newline.
+This is a non-portable extension.
+.It Ic O
+Pushes the output base on the top of the stack.
+.It Ic o
+The top value on the stack is popped and used as the
+base for further output.
+The initial output base is 10.
+.It Ic P
+The top of the stack is popped.
+If the top of the stack is a string, it is printed without a trailing newline.
+If the top of the stack is a number, it is interpreted as a
+base 256 number, and each digit of this base 256 number is printed as
+an
+.Tn ASCII
+character, without a trailing newline.
+.It Ic p
+The top value on the stack is printed with a trailing newline.
+The top value remains unchanged.
+.It Ic Q
+The top value on the stack is popped and the string execution level is popped
+by that value.
+.It Ic q
+Exits the program.
+If executing a string, the recursion level is
+popped by two.
+.It Ic R
+The top of the stack is removed (popped).
+This is a non-portable extension.
+.It Ic r
+The top two values on the stack are reversed (swapped).
+This is a non-portable extension.
+.It Ic S Ns Ar x
+Register
+.Ar x
+is treated as a stack.
+The top value of the main stack is popped and pushed on it.
+.It Ic s Ns Ar x
+The
+top of the stack is popped and stored into
+a register named
+.Ar x .
+.It Ic v
+Replaces the top element on the stack by its square root.
+The scale of the result is the maximum of the scale of the argument
+and the current value of scale.
+.It Ic X
+Replaces the number on the top of the stack with its scale factor.
+If the top of the stack is a string, replace it with the integer 0.
+.It Ic x
+Treats the top element of the stack as a character string
+and executes it as a string of
+.Nm
+commands.
+.It Ic Z
+Replaces the number on the top of the stack with its length.
+The length of a string is its number of characters.
+The length of a number is its number of digits, not counting the minus sign
+and decimal point.
+.It Ic z
+The stack level is pushed onto the stack.
+.It Cm [ Ns ... Ns Cm ]
+Puts the bracketed
+.Tn ASCII
+string onto the top of the stack.
+If the string includes brackets, these must be properly balanced.
+The backslash character
+.Pq Sq \e
+may be used as an escape character, making it
+possible to include unbalanced brackets in strings.
+To include a backslash in a string, use a double backslash.
+.It Xo
+.Cm < Ns Va x
+.Cm > Ns Va x
+.Cm = Ns Va x
+.Cm !< Ns Va x
+.Cm !> Ns Va x
+.Cm != Ns Va x
+.Xc
+The top two elements of the stack are popped and compared.
+Register
+.Ar x
+is executed if they obey the stated
+relation.
+.It Xo
+.Cm < Ns Va x Ns e Ns Va y
+.Cm > Ns Va x Ns e Ns Va y
+.Cm = Ns Va x Ns e Ns Va y
+.Cm !< Ns Va x Ns e Ns Va y
+.Cm !> Ns Va x Ns e Ns Va y
+.Cm != Ns Va x Ns e Ns Va y
+.Xc
+These operations are variants of the comparison operations above.
+The first register name is followed by the letter
+.Sq e
+and another register name.
+Register
+.Ar x
+will be executed if the relation is true, and register
+.Ar y
+will be executed if the relation is false.
+This is a non-portable extension.
+.It Ic \&(
+The top two numbers are popped from the stack and compared.
+A one is pushed if the top of the stack is less than the second number
+on the stack.
+A zero is pushed otherwise.
+This is a non-portable extension.
+.It Ic {
+The top two numbers are popped from the stack and compared.
+A one is pushed if the top of stack is less than or equal to the
+second number on the stack.
+A zero is pushed otherwise.
+This is a non-portable extension.
+.It Ic \&!
+Interprets the rest of the line as a
+.Ux
+command.
+.It Ic \&?
+A line of input is taken from the input source (usually the terminal)
+and executed.
+.It Ic : Ns Ar r
+Pop two values from the stack.
+The second value on the stack is stored into the array
+.Ar r
+indexed by the top of stack.
+.It Ic ; Ns Ar r
+Pop a value from the stack.
+The value is used as an index into register
+.Ar r .
+The value in this register is pushed onto the stack.
+.Pp
+Array elements initially have the value zero.
+Each level of a stacked register has its own array associated with
+it.
+The command sequence
+.Bd -literal -offset indent
+[first] 0:a [dummy] Sa [second] 0:a 0;a p La 0;a p
+.Ed
+.Pp
+will print
+.Bd -literal -offset indent
+second
+first
+.Ed
+.Pp
+since the string
+.Ql second
+is written in an array that is later popped, to reveal the array that
+stored
+.Ql first .
+.It Ic #
+Skip the rest of the line.
+This is a non-portable extension.
+.El
+.Ss Registers
+Registers have a single character name
+.Ar x ,
+where
+.Ar x
+may be any character, including space, tab or any other special character.
+If extended register mode is enabled using the
+.Fl x
+option and the register identifier
+.Ar x
+has the value 255, the next two characters are interpreted as a
+two-byte register index.
+The set of standard single character registers and the set of extended
+registers do not overlap.
+Extended register mode is a non-portable extension.
+.Sh EXAMPLES
+An example which prints the first ten values of
+.Ic n! :
+.Bd -literal -offset indent
+[la1+dsa*pla10>y]sy
+0sa1
+lyx
+.Ed
+.Pp
+Independent of the current input base, the command
+.Bd -literal -offset indent
+Ai
+.Ed
+.Pp
+will reset the input base to decimal 10.
+.Sh DIAGNOSTICS
+.Bl -diag
+.It %c (0%o) is unimplemented
+an undefined operation was called.
+.It stack empty
+for not enough elements on the stack to do what was asked.
+.It stack register '%c' (0%o) is empty
+for an
+.Ar L
+operation from a stack register that is empty.
+.It Runtime warning: non-zero scale in exponent
+for a fractional part of an exponent that is being ignored.
+.It divide by zero
+for trying to divide by zero.
+.It remainder by zero
+for trying to take a remainder by zero.
+.It square root of negative number
+for trying to take the square root of a negative number.
+.It index too big
+for an array index that is larger than 2048.
+.It negative index
+for a negative array index.
+.It "input base must be a number between 2 and 16"
+for trying to set an illegal input base.
+.It output base must be a number greater than 1
+for trying to set an illegal output base.
+.It scale must be a nonnegative number
+for trying to set a negative or zero scale.
+.It scale too large
+for trying to set a scale that is too large.
+A scale must be representable as a 32-bit unsigned number.
+.It Q command argument exceeded string execution depth
+for trying to pop the recursion level more than the current
+recursion level.
+.It Q command requires a number >= 1
+for trying to pop an illegal number of recursion levels.
+.It recursion too deep
+for too many levels of nested execution.
+.Pp
+The recursion level is increased by one if the
+.Ar x
+or
+.Ar ?\&
+operation or one of the compare operations resulting in the execution
+of register is executed.
+As an exception, the recursion level is not increased if the operation
+is executed as the last command of a string.
+For example, the commands
+.Bd -literal -offset indent
+[lax]sa
+1 lax
+.Ed
+.Pp
+will execute an endless loop, while the commands
+.Bd -literal -offset indent
+[laxp]sa
+1 lax
+.Ed
+.Pp
+will terminate because of a too deep recursion level.
+.It J command argument exceeded string execution depth
+for trying to pop the recursion level more than the current
+recursion level.
+.It mark not found
+for a failed scan for an occurrence of the
+.Ic M
+operator.
+.El
+.Sh SEE ALSO
+.Xr bc 1
+.Rs
+.%B USD:05
+.%A L. L. Cherry
+.%A R. Morris
+.%T "DC \- An Interactive Desk Calculator"
+.Re
+.Sh STANDARDS
+The arithmetic operations of the
+.Nm
+utility are expected to conform to the definition listed in the
+.Xr bc 1
+section of the
+.St -p1003.2
+specification.
+.Sh HISTORY
+The
+.Nm
+command first appeared in
+.At v6 .
+A complete rewrite of the
+.Nm
+command using the
+.Xr bn 3
+big number routines first appeared in
+.Ox 3.5 .
+.Sh AUTHORS
+.An -nosplit
+The original version of the
+.Nm
+command was written by
+.An Robert Morris
+and
+.An Lorinda Cherry .
+The current version of the
+.Nm
+utility was written by
+.An Otto Moerbeek .
diff --git a/usr.bin/dc/dc.c b/usr.bin/dc/dc.c
new file mode 100644
index 0000000..fd412b8
--- /dev/null
+++ b/usr.bin/dc/dc.c
@@ -0,0 +1,140 @@
+/*	$OpenBSD: dc.c,v 1.11 2009/10/27 23:59:37 deraadt Exp $	*/
+
+/*
+ * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
+ * Copyright (c) 2009, Gabor Kovesdan <gabor@FreeBSD.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/stat.h>
+
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "extern.h"
+
+#define	DC_VER		"1.3-FreeBSD"
+
+static void		 usage(void);
+
+extern char		*__progname;
+
+struct source		 src;
+
+struct option long_options[] =
+{
+	{"expression",		required_argument,	NULL,	'e'},
+	{"file",		required_argument,	NULL,	'f'},
+	{"help",		no_argument,		NULL,	'h'},
+	{"version",		no_argument,		NULL,	'V'}
+};
+
+static void
+usage(void)
+{
+	fprintf(stderr, "usage: %s [-hVx] [-e expression] [file]\n",
+	    __progname);
+	exit(1);
+}
+
+static void
+procfile(char *fname) {
+	FILE		*file;
+	struct stat	 st;
+
+	file = fopen(fname, "r");
+	if (file == NULL)
+		err(1, "cannot open file %s", fname);
+	if (fstat(fileno(file), &st) == -1)
+		err(1, "%s", fname);
+	if (S_ISDIR(st.st_mode)) {
+		errno = EISDIR;
+		err(1, "%s", fname);
+	}                
+	src_setstream(&src, file);
+	reset_bmachine(&src);
+	eval();
+	fclose(file);
+}
+
+int
+main(int argc, char *argv[])
+{
+	int		 ch;
+	bool		 extended_regs = false;
+	char		*buf;
+	bool		 preproc_done = false;
+
+	if ((buf = strdup("")) == NULL)
+		err(1, NULL);
+
+	init_bmachine(extended_regs);
+	setlinebuf(stdout);
+	setlinebuf(stderr);
+
+	/* accept and ignore a single dash to be 4.4BSD dc(1) compatible */
+	while ((ch = getopt_long(argc, argv, "e:f:Vx", long_options, NULL)) != -1) {
+		switch (ch) {
+		case 'e':
+			src_setstring(&src, optarg);
+			reset_bmachine(&src);
+			eval();
+			preproc_done = true;
+			break;
+		case 'f':
+			procfile(optarg);
+			preproc_done = true;
+			break;
+		case 'x':
+			extended_regs = true;
+			break;
+		case 'V':
+			fprintf(stderr, "%s (BSD bc) %s\n", __progname, DC_VER);
+			exit(0);
+			break;
+		case '-':
+			break;
+		case 'h':
+			/* FALLTHROUGH */
+		default:
+			usage();
+		}
+	}
+	argc -= optind;
+	argv += optind;
+
+	if (argc > 1)
+		usage();
+	if (argc == 1) {
+		procfile(argv[0]);
+		preproc_done = true;
+	}
+	if (preproc_done)
+		return (0);
+
+	src_setstream(&src, stdin);
+	reset_bmachine(&src);
+	eval();
+
+	return (0);
+}
diff --git a/usr.bin/dc/extern.h b/usr.bin/dc/extern.h
new file mode 100644
index 0000000..4abf063
--- /dev/null
+++ b/usr.bin/dc/extern.h
@@ -0,0 +1,63 @@
+/*	$FreeBSD$						*/
+/*	$OpenBSD: extern.h,v 1.3 2006/01/16 08:09:25 otto Exp $	*/
+
+/*
+ * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdbool.h>
+#include "bcode.h"
+
+
+/* inout.c */
+void		 src_setstream(struct source *, FILE *);
+void		 src_setstring(struct source *, char *);
+struct number	*readnumber(struct source *, u_int);
+void		 printnumber(FILE *, const struct number *, u_int);
+char		*read_string(struct source *);
+void		 print_value(FILE *, const struct value *, const char *, u_int);
+void		 print_ascii(FILE *, const struct number *);
+
+/* mem.c */
+struct number	*new_number(void);
+void		 free_number(struct number *);
+struct number	*dup_number(const struct number *);
+void		*bmalloc(size_t);
+void		*brealloc(void *, size_t);
+char		*bstrdup(const char *p);
+void		 bn_check(int);
+void		 bn_checkp(const void *);
+
+/* stack.c */
+void		 stack_init(struct stack *);
+void		 stack_free_value(struct value *);
+struct value	*stack_dup_value(const struct value *, struct value *);
+void		 stack_swap(struct stack *);
+size_t		 stack_size(const struct stack *);
+void		 stack_dup(struct stack *);
+void		 stack_pushnumber(struct stack *, struct number *);
+void		 stack_pushstring(struct stack *stack, char *);
+void	 	 stack_push(struct stack *, struct value *);
+void		 stack_set_tos(struct stack *, struct value *);
+struct value	*stack_tos(const struct stack *);
+struct value	*stack_pop(struct stack *);
+struct number	*stack_popnumber(struct stack *);
+char		*stack_popstring(struct stack *);
+void		 stack_clear(struct stack *);
+void		 stack_print(FILE *, const struct stack *, const char *,
+		    u_int base);
+void		 frame_assign(struct stack *, size_t, const struct value *);
+struct value	*frame_retrieve(const struct stack *, size_t);
+/* void		 frame_free(struct stack *); */
diff --git a/usr.bin/dc/inout.c b/usr.bin/dc/inout.c
new file mode 100644
index 0000000..b3239bc
--- /dev/null
+++ b/usr.bin/dc/inout.c
@@ -0,0 +1,417 @@
+/*	$OpenBSD: inout.c,v 1.15 2009/10/27 23:59:37 deraadt Exp $	*/
+
+/*
+ * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <openssl/ssl.h>
+#include <ctype.h>
+#include <err.h>
+#include <string.h>
+
+#include "extern.h"
+
+#define MAX_CHARS_PER_LINE 68
+
+static int	 lastchar;
+static int	 charcount;
+
+static int	 src_getcharstream(struct source *);
+static void	 src_ungetcharstream(struct source *);
+static char	*src_getlinestream(struct source *);
+static int	 src_getcharstring(struct source *);
+static void	 src_ungetcharstring(struct source *);
+static char	*src_getlinestring(struct source *);
+static void	 src_freestring(struct source *);
+static void	 flushwrap(FILE *);
+static void	 putcharwrap(FILE *, int);
+static void	 printwrap(FILE *, const char *);
+static char	*get_digit(u_long, int, u_int);
+
+static struct vtable stream_vtable = {
+	src_getcharstream,
+	src_ungetcharstream,
+	src_getlinestream,
+	NULL
+};
+
+static struct vtable string_vtable = {
+	src_getcharstring,
+	src_ungetcharstring,
+	src_getlinestring,
+	src_freestring
+};
+
+void
+src_setstream(struct source *src, FILE *stream)
+{
+
+	src->u.stream = stream;
+	src->vtable = &stream_vtable;
+}
+
+void
+src_setstring(struct source *src, char *p)
+{
+
+	src->u.string.buf = (u_char *)p;
+	src->u.string.pos = 0;
+	src->vtable = &string_vtable;
+}
+
+static int
+src_getcharstream(struct source *src)
+{
+
+	return (src->lastchar = getc(src->u.stream));
+}
+
+static void
+src_ungetcharstream(struct source *src)
+{
+
+	ungetc(src->lastchar, src->u.stream);
+}
+
+static char *
+src_getlinestream(struct source *src)
+{
+	char	 buf[BUFSIZ];
+
+	if (fgets(buf, BUFSIZ, src->u.stream) == NULL)
+		return (bstrdup(""));
+	return bstrdup(buf);
+}
+
+static int
+src_getcharstring(struct source *src)
+{
+
+	src->lastchar = src->u.string.buf[src->u.string.pos];
+	if (src->lastchar == '\0')
+		return (EOF);
+	else {
+		src->u.string.pos++;
+		return (src->lastchar);
+	}
+}
+
+static void
+src_ungetcharstring(struct source *src)
+{
+
+	if (src->u.string.pos > 0) {
+		if (src->lastchar != '\0')
+			--src->u.string.pos;
+	}
+}
+
+static char *
+src_getlinestring(struct source *src)
+{
+	char	 buf[BUFSIZ];
+	int	 ch, i;
+
+	i = 0;
+	while (i < BUFSIZ-1) {
+		ch = src_getcharstring(src);
+		if (ch == EOF)
+			break;
+		buf[i++] = ch;
+		if (ch == '\n')
+			break;
+	}
+	buf[i] = '\0';
+	return (bstrdup(buf));
+}
+
+static void
+src_freestring(struct source *src)
+{
+
+	free(src->u.string.buf);
+}
+
+static void
+flushwrap(FILE *f)
+{
+
+	if (lastchar != -1)
+		putc(lastchar, f);
+}
+
+static void
+putcharwrap(FILE *f, int ch)
+{
+
+	if (charcount >= MAX_CHARS_PER_LINE) {
+		charcount = 0;
+		fputs("\\\n", f);
+	}
+	if (lastchar != -1) {
+		charcount++;
+		putc(lastchar, f);
+	}
+	lastchar = ch;
+}
+
+static void
+printwrap(FILE *f, const char *p)
+{
+	char	 buf[12];
+	char	*q = buf;
+
+	strlcpy(buf, p, sizeof(buf));
+	while (*q)
+		putcharwrap(f, *q++);
+}
+
+struct number *
+readnumber(struct source *src, u_int base)
+{
+	struct number	*n;
+	int		 ch;
+	bool		 sign = false;
+	bool		 dot = false;
+	BN_ULONG	 v;
+	u_int		 i;
+
+	n = new_number();
+	bn_check(BN_zero(n->number));
+
+	while ((ch = (*src->vtable->readchar)(src)) != EOF) {
+
+		if ('0' <= ch && ch <= '9')
+			v = ch - '0';
+		else if ('A' <= ch && ch <= 'F')
+			v = ch - 'A' + 10;
+		else if (ch == '_') {
+			sign = true;
+			continue;
+		} else if (ch == '.') {
+			if (dot)
+				break;
+			dot = true;
+			continue;
+		} else {
+			(*src->vtable->unreadchar)(src);
+			break;
+		}
+		if (dot)
+			n->scale++;
+
+		bn_check(BN_mul_word(n->number, base));
+
+#if 0
+		/* work around a bug in BN_add_word: 0 += 0 is buggy.... */
+		if (v > 0)
+#endif
+			bn_check(BN_add_word(n->number, v));
+	}
+	if (base != 10) {
+		scale_number(n->number, n->scale);
+		for (i = 0; i < n->scale; i++)
+			BN_div_word(n->number, base);
+	}
+	if (sign)
+		negate(n);
+	return (n);
+}
+
+char *
+read_string(struct source *src)
+{
+	int	 count, i, sz, new_sz, ch;
+	char	*p;
+	bool	 escape;
+
+	escape = false;
+	count = 1;
+	i = 0;
+	sz = 15;
+	p = bmalloc(sz + 1);
+
+	while ((ch = (*src->vtable->readchar)(src)) != EOF) {
+		if (!escape) {
+			if (ch == '[')
+				count++;
+			else if (ch == ']')
+				count--;
+			if (count == 0)
+				break;
+		}
+		if (ch == '\\' && !escape)
+			escape = true;
+		else {
+			escape = false;
+			if (i == sz) {
+				new_sz = sz * 2;
+				p = brealloc(p, new_sz + 1);
+				sz = new_sz;
+			}
+			p[i++] = ch;
+		}
+	}
+	p[i] = '\0';
+	return (p);
+}
+
+static char *
+get_digit(u_long num, int digits, u_int base)
+{
+	char	*p;
+
+	if (base <= 16) {
+		p = bmalloc(2);
+		p[0] = num >= 10 ? num + 'A' - 10 : num + '0';
+		p[1] = '\0';
+	} else {
+		if (asprintf(&p, "%0*lu", digits, num) == -1)
+			err(1, NULL);
+	}
+	return (p);
+}
+
+void
+printnumber(FILE *f, const struct number *b, u_int base)
+{
+	struct number	*int_part, *fract_part;
+	int		 digits;
+	char		 buf[11];
+	size_t		 sz;
+	unsigned int	 i;
+	struct stack	 stack;
+	char		*p;
+
+	charcount = 0;
+	lastchar = -1;
+	if (BN_is_zero(b->number))
+		putcharwrap(f, '0');
+
+	int_part = new_number();
+	fract_part = new_number();
+	fract_part->scale = b->scale;
+
+	if (base <= 16)
+		digits = 1;
+	else {
+		digits = snprintf(buf, sizeof(buf), "%u", base-1);
+	}
+	split_number(b, int_part->number, fract_part->number);
+
+	i = 0;
+	stack_init(&stack);
+	while (!BN_is_zero(int_part->number)) {
+		BN_ULONG rem = BN_div_word(int_part->number, base);
+		stack_pushstring(&stack, get_digit(rem, digits, base));
+		i++;
+	}
+	sz = i;
+	if (BN_cmp(b->number, &zero) < 0)
+		putcharwrap(f, '-');
+	for (i = 0; i < sz; i++) {
+		p = stack_popstring(&stack);
+		if (base > 16)
+			putcharwrap(f, ' ');
+		printwrap(f, p);
+		free(p);
+	}
+	stack_clear(&stack);
+	if (b->scale > 0) {
+		struct number	*num_base;
+		BIGNUM		 mult, stop;
+
+		putcharwrap(f, '.');
+		num_base = new_number();
+		bn_check(BN_set_word(num_base->number, base));
+		BN_init(&mult);
+		bn_check(BN_one(&mult));
+		BN_init(&stop);
+		bn_check(BN_one(&stop));
+		scale_number(&stop, b->scale);
+
+		i = 0;
+		while (BN_cmp(&mult, &stop) < 0) {
+			u_long	 rem;
+
+			if (i && base > 16)
+				putcharwrap(f, ' ');
+			i = 1;
+
+			bmul_number(fract_part, fract_part, num_base);
+			split_number(fract_part, int_part->number, NULL);
+			rem = BN_get_word(int_part->number);
+			p = get_digit(rem, digits, base);
+			int_part->scale = 0;
+			normalize(int_part, fract_part->scale);
+			bn_check(BN_sub(fract_part->number, fract_part->number,
+			    int_part->number));
+			printwrap(f, p);
+			free(p);
+			bn_check(BN_mul_word(&mult, base));
+		}
+		free_number(num_base);
+		BN_free(&mult);
+		BN_free(&stop);
+	}
+	flushwrap(f);
+	free_number(int_part);
+	free_number(fract_part);
+}
+
+void
+print_value(FILE *f, const struct value *value, const char *prefix, u_int base)
+{
+
+	fputs(prefix, f);
+	switch (value->type) {
+	case BCODE_NONE:
+		if (value->array != NULL)
+			fputs("<array>", f);
+		break;
+	case BCODE_NUMBER:
+		printnumber(f, value->u.num, base);
+		break;
+	case BCODE_STRING:
+		fputs(value->u.string, f);
+		break;
+	}
+}
+
+void
+print_ascii(FILE *f, const struct number *n)
+{
+	BIGNUM		*v;
+	int		 numbits, i, ch;
+
+	v = BN_dup(n->number);
+	bn_checkp(v);
+
+	if (BN_cmp(v, &zero) < 0)
+		bn_check(BN_sub(v, &zero, v));
+
+	numbits = BN_num_bytes(v) * 8;
+	while (numbits > 0) {
+		ch = 0;
+		for (i = 0; i < 8; i++)
+			ch |= BN_is_bit_set(v, numbits-i-1) << (7 - i);
+		putc(ch, f);
+		numbits -= 8;
+	}
+	BN_free(v);
+}
diff --git a/usr.bin/dc/mem.c b/usr.bin/dc/mem.c
new file mode 100644
index 0000000..364d674
--- /dev/null
+++ b/usr.bin/dc/mem.c
@@ -0,0 +1,110 @@
+/*	$OpenBSD: mem.c,v 1.5 2009/10/27 23:59:37 deraadt Exp $	*/
+
+/*
+ * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <openssl/err.h>
+
+#include <err.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "extern.h"
+
+struct number *
+new_number(void)
+{
+	struct number	*n;
+
+	n = bmalloc(sizeof(*n));
+	n->scale = 0;
+	n->number = BN_new();
+	if (n->number == NULL)
+		err(1, NULL);
+	return (n);
+}
+
+void
+free_number(struct number *n)
+{
+
+	BN_free(n->number);
+	free(n);
+}
+
+struct number *
+dup_number(const struct number *a)
+{
+	struct number	*n;
+
+	n = bmalloc(sizeof(*n));
+	n->scale = a->scale;
+	n->number = BN_dup(a->number);
+	bn_checkp(n->number);
+	return (n);
+}
+
+void *
+bmalloc(size_t sz)
+{
+	void	*p;
+
+	p = malloc(sz);
+	if (p == NULL)
+		err(1, NULL);
+	return (p);
+}
+
+void *
+brealloc(void *p, size_t sz)
+{
+	void	*q;
+
+	q = realloc(p, sz);
+	if (q == NULL)
+		err(1, NULL);
+	return (q);
+}
+
+char *
+bstrdup(const char *p)
+{
+	char	*q;
+
+	q = strdup(p);
+	if (q == NULL)
+		err(1, NULL);
+	return (q);
+}
+
+void
+bn_check(int x)						\
+{
+
+	if (x == 0)
+		err(1, "big number failure %lx", ERR_get_error());
+}
+
+void
+bn_checkp(const void *p)						\
+{
+
+	if (p == NULL)
+		err(1, "allocation failure %lx", ERR_get_error());
+}
diff --git a/usr.bin/dc/stack.c b/usr.bin/dc/stack.c
new file mode 100644
index 0000000..775c563
--- /dev/null
+++ b/usr.bin/dc/stack.c
@@ -0,0 +1,379 @@
+/*	$OpenBSD: stack.c,v 1.11 2009/10/27 23:59:37 deraadt Exp $	*/
+
+/*
+ * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <err.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "extern.h"
+
+static __inline bool	 stack_empty(const struct stack *);
+static void		 stack_grow(struct stack *);
+static struct array	*array_new(void);
+static __inline void	 array_free(struct array *);
+static struct array	*array_dup(const struct array *);
+static __inline void	 array_grow(struct array *, size_t);
+static __inline void	 array_assign(struct array *, size_t, const struct value *);
+static __inline struct value	*array_retrieve(const struct array *, size_t);
+
+void
+stack_init(struct stack *stack)
+{
+
+	stack->size = 0;
+	stack->sp = -1;
+	stack->stack = NULL;
+}
+
+static __inline bool
+stack_empty(const struct stack *stack)
+{
+	bool	 empty = stack->sp == -1;
+
+	if (empty)
+		warnx("stack empty");
+	return empty;
+}
+
+/* Clear number or string, but leave value itself */
+void
+stack_free_value(struct value *v)
+{
+
+	switch (v->type) {
+	case BCODE_NONE:
+		break;
+	case BCODE_NUMBER:
+		free_number(v->u.num);
+		break;
+	case BCODE_STRING:
+		free(v->u.string);
+		break;
+	}
+	if (v->array != NULL) {
+		array_free(v->array);
+		v->array = NULL;
+	}
+}
+
+/* Copy number or string content into already allocated target */
+struct value *
+stack_dup_value(const struct value *a, struct value *copy)
+{
+
+	copy->type = a->type;
+
+	switch (a->type) {
+	case BCODE_NONE:
+		break;
+	case BCODE_NUMBER:
+		copy->u.num = dup_number(a->u.num);
+		break;
+	case BCODE_STRING:
+		copy->u.string = strdup(a->u.string);
+		if (copy->u.string == NULL)
+			err(1, NULL);
+		break;
+	}
+
+	copy->array = a->array == NULL ? NULL : array_dup(a->array);
+
+	return (copy);
+}
+
+size_t
+stack_size(const struct stack *stack)
+{
+
+	return (stack->sp + 1);
+}
+
+void
+stack_dup(struct stack *stack)
+{
+	struct value	*value;
+	struct value	 copy;
+
+	value = stack_tos(stack);
+	if (value == NULL) {
+		warnx("stack empty");
+		return;
+	}
+	stack_push(stack, stack_dup_value(value, &copy));
+}
+
+void
+stack_swap(struct stack *stack)
+{
+	struct value	 copy;
+
+	if (stack->sp < 1) {
+		warnx("stack empty");
+		return;
+	}
+	copy = stack->stack[stack->sp];
+	stack->stack[stack->sp] = stack->stack[stack->sp-1];
+	stack->stack[stack->sp-1] = copy;
+}
+
+static void
+stack_grow(struct stack *stack)
+{
+	size_t	 new_size, i;
+
+	if (++stack->sp == stack->size) {
+		new_size = stack->size * 2 + 1;
+		stack->stack = brealloc(stack->stack,
+		    new_size * sizeof(*stack->stack));
+		for (i = stack->size; i < new_size; i++)
+			stack->stack[i].array = NULL;
+		stack->size = new_size;
+	}
+}
+
+void
+stack_pushnumber(struct stack *stack, struct number *b)
+{
+
+	stack_grow(stack);
+	stack->stack[stack->sp].type = BCODE_NUMBER;
+	stack->stack[stack->sp].u.num = b;
+}
+
+void
+stack_pushstring(struct stack *stack, char *string)
+{
+
+	stack_grow(stack);
+	stack->stack[stack->sp].type = BCODE_STRING;
+	stack->stack[stack->sp].u.string = string;
+}
+
+void
+stack_push(struct stack *stack, struct value *v)
+{
+
+	switch (v->type) {
+	case BCODE_NONE:
+		stack_grow(stack);
+		stack->stack[stack->sp].type = BCODE_NONE;
+		break;
+	case BCODE_NUMBER:
+		stack_pushnumber(stack, v->u.num);
+		break;
+	case BCODE_STRING:
+		stack_pushstring(stack, v->u.string);
+		break;
+	}
+	stack->stack[stack->sp].array = v->array == NULL ?
+	    NULL : array_dup(v->array);
+}
+
+struct value *
+stack_tos(const struct stack *stack)
+{
+
+	if (stack->sp == -1)
+		return (NULL);
+	return &stack->stack[stack->sp];
+}
+
+void
+stack_set_tos(struct stack *stack, struct value *v)
+{
+
+	if (stack->sp == -1)
+		stack_push(stack, v);
+	else {
+		stack_free_value(&stack->stack[stack->sp]);
+		stack->stack[stack->sp] = *v;
+		stack->stack[stack->sp].array = v->array == NULL ?
+		    NULL : array_dup(v->array);
+	}
+}
+
+struct value *
+stack_pop(struct stack *stack)
+{
+
+	if (stack_empty(stack))
+		return (NULL);
+	return &stack->stack[stack->sp--];
+}
+
+struct number *
+stack_popnumber(struct stack *stack)
+{
+
+	if (stack_empty(stack))
+		return (NULL);
+	if (stack->stack[stack->sp].array != NULL) {
+		array_free(stack->stack[stack->sp].array);
+		stack->stack[stack->sp].array = NULL;
+	}
+	if (stack->stack[stack->sp].type != BCODE_NUMBER) {
+		warnx("not a number"); /* XXX remove */
+		return (NULL);
+	}
+	return stack->stack[stack->sp--].u.num;
+}
+
+char *
+stack_popstring(struct stack *stack)
+{
+
+	if (stack_empty(stack))
+		return (NULL);
+	if (stack->stack[stack->sp].array != NULL) {
+		array_free(stack->stack[stack->sp].array);
+		stack->stack[stack->sp].array = NULL;
+	}
+	if (stack->stack[stack->sp].type != BCODE_STRING) {
+		warnx("not a string"); /* XXX remove */
+		return (NULL);
+	}
+	return stack->stack[stack->sp--].u.string;
+}
+
+void
+stack_clear(struct stack *stack)
+{
+
+	while (stack->sp >= 0) {
+		stack_free_value(&stack->stack[stack->sp--]);
+	}
+	free(stack->stack);
+	stack_init(stack);
+}
+
+void
+stack_print(FILE *f, const struct stack *stack, const char *prefix, u_int base)
+{
+	ssize_t	 i;
+
+	for (i = stack->sp; i >= 0; i--) {
+		print_value(f, &stack->stack[i], prefix, base);
+		putc('\n', f);
+	}
+}
+
+
+static struct array *
+array_new(void)
+{
+	struct array	*a;
+
+	a = bmalloc(sizeof(*a));
+	a->data = NULL;
+	a->size = 0;
+	return a;
+}
+
+static __inline void
+array_free(struct array *a)
+{
+	size_t	 i;
+
+	if (a == NULL)
+		return;
+	for (i = 0; i < a->size; i++)
+		stack_free_value(&a->data[i]);
+	free(a->data);
+	free(a);
+}
+
+static struct array *
+array_dup(const struct array *a)
+{
+	struct array	*n;
+	size_t		 i;
+
+	if (a == NULL)
+		return (NULL);
+	n = array_new();
+	array_grow(n, a->size);
+	for (i = 0; i < a->size; i++)
+		stack_dup_value(&a->data[i], &n->data[i]);
+	return (n);
+}
+
+static __inline void
+array_grow(struct array *array, size_t newsize)
+{
+	size_t	 i;
+
+	array->data = brealloc(array->data, newsize * sizeof(*array->data));
+	for (i = array->size; i < newsize; i++) {
+		array->data[i].type = BCODE_NONE;
+		array->data[i].array = NULL;
+	}
+	array->size = newsize;
+}
+
+static __inline void
+array_assign(struct array *array, size_t i, const struct value *v)
+{
+
+	if (i >= array->size)
+		array_grow(array, i + 1);
+	stack_free_value(&array->data[i]);
+	array->data[i] = *v;
+}
+
+static __inline struct value *
+array_retrieve(const struct array *array, size_t i)
+{
+
+	if (i >= array->size)
+		return (NULL);
+	return &array->data[i];
+}
+
+void
+frame_assign(struct stack *stack, size_t i, const struct value *v)
+{
+	struct array	*a;
+	struct value	 n;
+
+	if (stack->sp == -1) {
+		n.type = BCODE_NONE;
+		n.array = NULL;
+		stack_push(stack, &n);
+	}
+
+	a = stack->stack[stack->sp].array;
+	if (a == NULL)
+		a = stack->stack[stack->sp].array = array_new();
+	array_assign(a, i, v);
+}
+
+struct value *
+frame_retrieve(const struct stack *stack, size_t i)
+{
+	struct array	*a;
+
+	if (stack->sp == -1)
+		return (NULL);
+	a = stack->stack[stack->sp].array;
+	if (a == NULL)
+		a = stack->stack[stack->sp].array = array_new();
+	return array_retrieve(a, i);
+}