diff options
author | harti <harti@FreeBSD.org> | 2005-02-04 16:48:35 +0000 |
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committer | harti <harti@FreeBSD.org> | 2005-02-04 16:48:35 +0000 |
commit | 44af3ae9764173adf195a782e9a44aba443970bc (patch) | |
tree | 0a0f1c1f65bd5e5748f9c127069bafe77238ff39 /usr.bin/make/buf.c | |
parent | 71c4337044da4b38ff33a8264907ee9b3cfe4847 (diff) | |
download | FreeBSD-src-44af3ae9764173adf195a782e9a44aba443970bc.zip FreeBSD-src-44af3ae9764173adf195a782e9a44aba443970bc.tar.gz |
Rewrite of the buf code:
- convert Buf_AddByte from a macro to a function
- move #define's into the header file
- remove unused field in struct Buffer
- remove size fields - they can be easily computed
- inline Buf_OvAddByte
Submitted by: Max Okumoto <okumoto@ucsd.edu>
Diffstat (limited to 'usr.bin/make/buf.c')
-rw-r--r-- | usr.bin/make/buf.c | 244 |
1 files changed, 88 insertions, 156 deletions
diff --git a/usr.bin/make/buf.c b/usr.bin/make/buf.c index c4294bd..3327c7f 100644 --- a/usr.bin/make/buf.c +++ b/usr.bin/make/buf.c @@ -1,4 +1,5 @@ /*- + * Copyright (c) 2005 Max Okumoto * Copyright (c) 1988, 1989, 1990, 1993 * The Regents of the University of California. All rights reserved. * Copyright (c) 1988, 1989 by Adam de Boor @@ -42,8 +43,8 @@ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); -/*- - * buf.c -- +/* + * buf.c * Functions for automatically-expanded buffers. */ @@ -54,220 +55,151 @@ __FBSDID("$FreeBSD$"); #include "sprite.h" #include "util.h" -#ifndef max -#define max(a,b) ((a) > (b) ? (a) : (b)) +#ifndef MAX +#define MAX(a,b) ((a) > (b) ? (a) : (b)) #endif -/* - * BufExpand -- - * Expand the given buffer to hold the given number of additional - * bytes. - * Makes sure there's room for an extra NULL byte at the end of the - * buffer in case it holds a string. +/** + * Returns the number of bytes in the buffer. Doesn't include the + * null-terminating byte. */ -#define BufExpand(bp, nb) do { \ - if ((bp)->left < (nb) + 1) { \ - int newSize = (bp)->size + max((nb) + 1, BUF_ADD_INC); \ - Byte *newBuf = erealloc((bp)->buffer, newSize); \ - \ - (bp)->inPtr = newBuf + ((bp)->inPtr - (bp)->buffer); \ - (bp)->outPtr = newBuf + ((bp)->outPtr - (bp)->buffer); \ - (bp)->buffer = newBuf; \ - (bp)->size = newSize; \ - (bp)->left = newSize - ((bp)->inPtr - (bp)->buffer); \ - } \ - } while (0) +inline size_t +Buf_Size(const Buffer *buf) +{ -#define BUF_DEF_SIZE 256 /* Default buffer size */ -#define BUF_ADD_INC 256 /* Expansion increment when Adding */ -#define BUF_UNGET_INC 16 /* Expansion increment when Ungetting */ + return (buf->end - buf->buf); +} -/*- - *----------------------------------------------------------------------- - * Buf_OvAddByte -- - * Add a single byte to the buffer. left is zero or negative. - * - * Results: - * None. - * - * Side Effects: - * The buffer may be expanded. - * - *----------------------------------------------------------------------- +/** + * Expand the buffer to hold the number of additional bytes, plus + * space to store a terminating NULL byte. */ -void -Buf_OvAddByte(Buffer *bp, Byte byte) +static inline void +BufExpand(Buffer *bp, size_t nb) { - - bp->left = 0; - BufExpand(bp, 1); - - *bp->inPtr++ = byte; - bp->left--; - - /* - * Null-terminate - */ - *bp->inPtr = 0; + size_t len = Buf_Size(bp); + size_t size; + + if (bp->size < len + nb + 1) { + size = bp->size + MAX(nb + 1, BUF_ADD_INC); + bp->size = size; + bp->buf = erealloc(bp->buf, size); + bp->end = bp->buf + len; + } } -/*- - *----------------------------------------------------------------------- - * Buf_AddBytes -- - * Add a number of bytes to the buffer. - * - * Results: - * None. - * - * Side Effects: - * Guess what? - * - *----------------------------------------------------------------------- +/** + * Add a single byte to the buffer. */ -void -Buf_AddBytes(Buffer *bp, size_t numBytes, const Byte *bytesPtr) +inline void +Buf_AddByte(Buffer *bp, Byte byte) { - BufExpand(bp, numBytes); - - memcpy(bp->inPtr, bytesPtr, numBytes); - bp->inPtr += numBytes; - bp->left -= numBytes; + BufExpand(bp, 1); - /* - * Null-terminate - */ - *bp->inPtr = 0; + *bp->end = byte; + bp->end++; + *bp->end = '\0'; } -/*- - *----------------------------------------------------------------------- - * Buf_GetAll -- - * Get all the available data at once. - * - * Results: - * A pointer to the data and the number of bytes available. - * - * Side Effects: - * None. - * - *----------------------------------------------------------------------- +/** + * Add bytes to the buffer. */ -Byte * -Buf_GetAll(Buffer *bp, size_t *numBytesPtr) +void +Buf_AddBytes(Buffer *bp, size_t len, const Byte *bytes) { - if (numBytesPtr != NULL) - *numBytesPtr = bp->inPtr - bp->outPtr; + BufExpand(bp, len); - return (bp->outPtr); + memcpy(bp->end, bytes, len); + bp->end += len; + *bp->end = '\0'; } -/*- - *----------------------------------------------------------------------- - * Buf_Size -- - * Returns the number of bytes in the given buffer. Doesn't include - * the null-terminating byte. - * - * Results: - * The number of bytes. +/** + * Get a reference to the internal buffer. * - * Side Effects: - * None. + * len: + * Pointer to where we return the number of bytes in the internal buffer. * - *----------------------------------------------------------------------- + * Returns: + * return A pointer to the data. */ -size_t -Buf_Size(Buffer *buf) +Byte * +Buf_GetAll(Buffer *bp, size_t *len) { - return (buf->inPtr - buf->outPtr); + if (len != NULL) + *len = Buf_Size(bp); + + return (bp->buf); } -/*- - *----------------------------------------------------------------------- - * Buf_Init -- - * Initialize a buffer. If no initial size is given, a reasonable - * default is used. +/** + * Initialize a buffer. If no initial size is given, a reasonable + * default is used. * - * Results: - * A buffer to be given to other functions in this library. + * Returns: + * A buffer object to be given to other functions in this library. * * Side Effects: - * The buffer is created, the space allocated and pointers - * initialized. - * - *----------------------------------------------------------------------- + * Space is allocated for the Buffer object and a internal buffer. */ Buffer * Buf_Init(size_t size) { - Buffer *bp; /* New Buffer */ - - bp = emalloc(sizeof(*bp)); + Buffer *bp; /* New Buffer */ if (size <= 0) size = BUF_DEF_SIZE; - bp->left = bp->size = size; - bp->buffer = emalloc(size); - bp->inPtr = bp->outPtr = bp->buffer; - *bp->inPtr = 0; + bp = emalloc(sizeof(*bp)); + bp->size = size; + bp->buf = emalloc(size); + bp->end = bp->buf; + *bp->end = '\0'; return (bp); } -/*- - *----------------------------------------------------------------------- - * Buf_Destroy -- - * Destroy a buffer, and optionally free its data, too. - * - * Results: - * None. +/** + * Destroy a buffer, and optionally free its data, too. * * Side Effects: - * The buffer is freed. - * - *----------------------------------------------------------------------- + * Space for the Buffer object and possibly the internal buffer + * is de-allocated. */ void Buf_Destroy(Buffer *buf, Boolean freeData) { if (freeData) - free(buf->buffer); + free(buf->buf); free(buf); } -/*- - *----------------------------------------------------------------------- - * Buf_ReplaceLastByte -- - * Replace the last byte in a buffer. - * - * Results: - * None. - * - * Side Effects: - * If the buffer was empty intially, then a new byte will be added. - * Otherwise, the last byte is overwritten. - * - *----------------------------------------------------------------------- +/** + * Replace the last byte in a buffer. If the buffer was empty + * intially, then a new byte will be added. */ void -Buf_ReplaceLastByte(Buffer *buf, Byte byte) +Buf_ReplaceLastByte(Buffer *bp, Byte byte) { - if (buf->inPtr == buf->outPtr) - Buf_AddByte(buf, byte); - else - *(buf->inPtr - 1) = byte; + + if (bp->end == bp->buf) { + Buf_AddByte(bp, byte); + } else { + *(bp->end - 1) = byte; + } } +/** + * Clear the contents of the buffer. + */ void Buf_Clear(Buffer *bp) { - bp->inPtr = bp->buffer; - bp->outPtr = bp->buffer; - bp->left = bp->size; - bp->inPtr[0] = '\0'; -} + bp->end = bp->buf; + *bp->end = '\0'; +} |