diff options
Diffstat (limited to 'usr.bin/sed/process.c')
-rw-r--r-- | usr.bin/sed/process.c | 629 |
1 files changed, 629 insertions, 0 deletions
diff --git a/usr.bin/sed/process.c b/usr.bin/sed/process.c new file mode 100644 index 0000000..2ec8aac --- /dev/null +++ b/usr.bin/sed/process.c @@ -0,0 +1,629 @@ +/*- + * Copyright (c) 1992 Diomidis Spinellis. + * Copyright (c) 1992, 1993, 1994 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Diomidis Spinellis of Imperial College, University of London. + * + * 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 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 by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 THE REGENTS OR CONTRIBUTORS 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. + */ + +#ifndef lint +static char sccsid[] = "@(#)process.c 8.6 (Berkeley) 4/20/94"; +#endif /* not lint */ + +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/ioctl.h> +#include <sys/uio.h> + +#include <ctype.h> +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <regex.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "defs.h" +#include "extern.h" + +static SPACE HS, PS, SS; +#define pd PS.deleted +#define ps PS.space +#define psl PS.len +#define hs HS.space +#define hsl HS.len + +static inline int applies __P((struct s_command *)); +static void flush_appends __P((void)); +static void lputs __P((char *)); +static inline int regexec_e __P((regex_t *, const char *, int, int, size_t)); +static void regsub __P((SPACE *, char *, char *)); +static int substitute __P((struct s_command *)); + +struct s_appends *appends; /* Array of pointers to strings to append. */ +static int appendx; /* Index into appends array. */ +int appendnum; /* Size of appends array. */ + +static int lastaddr; /* Set by applies if last address of a range. */ +static int sdone; /* If any substitutes since last line input. */ + /* Iov structure for 'w' commands. */ +static regex_t *defpreg; +size_t maxnsub; +regmatch_t *match; + +#define OUT(s) { fwrite(s, sizeof(u_char), psl, stdout); } + +void +process() +{ + struct s_command *cp; + SPACE tspace; + size_t len; + char oldc, *p; + + for (linenum = 0; mf_fgets(&PS, REPLACE);) { + pd = 0; + cp = prog; +redirect: + while (cp != NULL) { + if (!applies(cp)) { + cp = cp->next; + continue; + } + switch (cp->code) { + case '{': + cp = cp->u.c; + goto redirect; + case 'a': + if (appendx >= appendnum) + appends = xrealloc(appends, + sizeof(struct s_appends) * + (appendnum *= 2)); + appends[appendx].type = AP_STRING; + appends[appendx].s = cp->t; + appends[appendx].len = strlen(cp->t); + appendx++; + break; + case 'b': + cp = cp->u.c; + goto redirect; + case 'c': + pd = 1; + psl = 0; + if (cp->a2 == NULL || lastaddr) + (void)printf("%s", cp->t); + break; + case 'd': + pd = 1; + goto new; + case 'D': + if (pd) + goto new; + if ((p = memchr(ps, '\n', psl)) == NULL) + pd = 1; + else { + psl -= (p - ps) + 1; + memmove(ps, p + 1, psl); + } + goto new; + case 'g': + cspace(&PS, hs, hsl, REPLACE); + break; + case 'G': + cspace(&PS, hs, hsl, 0); + break; + case 'h': + cspace(&HS, ps, psl, REPLACE); + break; + case 'H': + cspace(&HS, ps, psl, 0); + break; + case 'i': + (void)printf("%s", cp->t); + break; + case 'l': + lputs(ps); + break; + case 'n': + if (!nflag && !pd) + OUT(ps) + flush_appends(); + if (!mf_fgets(&PS, REPLACE)) + exit(0); + pd = 0; + break; + case 'N': + flush_appends(); + if (!mf_fgets(&PS, 0)) { + if (!nflag && !pd) + OUT(ps) + exit(0); + } + break; + case 'p': + if (pd) + break; + OUT(ps) + break; + case 'P': + if (pd) + break; + if ((p = memchr(ps, '\n', psl)) != NULL) { + oldc = *p; + *p = '\0'; + } + OUT(ps) + if (p != NULL) + *p = oldc; + break; + case 'q': + if (!nflag && !pd) + OUT(ps) + flush_appends(); + exit(0); + case 'r': + if (appendx >= appendnum) + appends = xrealloc(appends, + sizeof(struct s_appends) * + (appendnum *= 2)); + appends[appendx].type = AP_FILE; + appends[appendx].s = cp->t; + appends[appendx].len = strlen(cp->t); + appendx++; + break; + case 's': + sdone |= substitute(cp); + break; + case 't': + if (sdone) { + sdone = 0; + cp = cp->u.c; + goto redirect; + } + break; + case 'w': + if (pd) + break; + if (cp->u.fd == -1 && (cp->u.fd = open(cp->t, + O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, + DEFFILEMODE)) == -1) + err(FATAL, "%s: %s\n", + cp->t, strerror(errno)); + if (write(cp->u.fd, ps, psl) != psl) + err(FATAL, "%s: %s\n", + cp->t, strerror(errno)); + break; + case 'x': + if (hs == NULL) + cspace(&HS, "", 0, REPLACE); + tspace = PS; + PS = HS; + HS = tspace; + break; + case 'y': + if (pd) + break; + for (p = ps, len = psl; --len; ++p) + *p = cp->u.y[*p]; + break; + case ':': + case '}': + break; + case '=': + (void)printf("%lu\n", linenum); + } + cp = cp->next; + } /* for all cp */ + +new: if (!nflag && !pd) + OUT(ps) + flush_appends(); + } /* for all lines */ +} + +/* + * TRUE if the address passed matches the current program state + * (lastline, linenumber, ps). + */ +#define MATCH(a) \ + (a)->type == AT_RE ? regexec_e((a)->u.r, ps, 0, 1, psl) : \ + (a)->type == AT_LINE ? linenum == (a)->u.l : lastline + +/* + * Return TRUE if the command applies to the current line. Sets the inrange + * flag to process ranges. Interprets the non-select (``!'') flag. + */ +static inline int +applies(cp) + struct s_command *cp; +{ + int r; + + lastaddr = 0; + if (cp->a1 == NULL && cp->a2 == NULL) + r = 1; + else if (cp->a2) + if (cp->inrange) { + if (MATCH(cp->a2)) { + cp->inrange = 0; + lastaddr = 1; + } + r = 1; + } else if (MATCH(cp->a1)) { + /* + * If the second address is a number less than or + * equal to the line number first selected, only + * one line shall be selected. + * -- POSIX 1003.2 + */ + if (cp->a2->type == AT_LINE && + linenum >= cp->a2->u.l) + lastaddr = 1; + else + cp->inrange = 1; + r = 1; + } else + r = 0; + else + r = MATCH(cp->a1); + return (cp->nonsel ? ! r : r); +} + +/* + * substitute -- + * Do substitutions in the pattern space. Currently, we build a + * copy of the new pattern space in the substitute space structure + * and then swap them. + */ +static int +substitute(cp) + struct s_command *cp; +{ + SPACE tspace; + regex_t *re; + size_t re_off, slen; + int lastempty, n; + char *s; + + s = ps; + re = cp->u.s->re; + if (re == NULL) { + if (defpreg != NULL && cp->u.s->maxbref > defpreg->re_nsub) { + linenum = cp->u.s->linenum; + err(COMPILE, "\\%d not defined in the RE", + cp->u.s->maxbref); + } + } + if (!regexec_e(re, s, 0, 0, psl)) + return (0); + + SS.len = 0; /* Clean substitute space. */ + slen = psl; + n = cp->u.s->n; + lastempty = 1; + + switch (n) { + case 0: /* Global */ + do { + if (lastempty || match[0].rm_so != match[0].rm_eo) { + /* Locate start of replaced string. */ + re_off = match[0].rm_so; + /* Copy leading retained string. */ + cspace(&SS, s, re_off, APPEND); + /* Add in regular expression. */ + regsub(&SS, s, cp->u.s->new); + } + + /* Move past this match. */ + if (match[0].rm_so != match[0].rm_eo) { + s += match[0].rm_eo; + slen -= match[0].rm_eo; + lastempty = 0; + } else { + if (match[0].rm_so == 0) + cspace(&SS, + s, match[0].rm_so + 1, APPEND); + else + cspace(&SS, + s + match[0].rm_so, 1, APPEND); + s += match[0].rm_so + 1; + slen -= match[0].rm_so + 1; + lastempty = 1; + } + } while (slen > 0 && regexec_e(re, s, REG_NOTBOL, 0, slen)); + /* Copy trailing retained string. */ + if (slen > 0) + cspace(&SS, s, slen, APPEND); + break; + default: /* Nth occurrence */ + while (--n) { + s += match[0].rm_eo; + slen -= match[0].rm_eo; + if (!regexec_e(re, s, REG_NOTBOL, 0, slen)) + return (0); + } + /* FALLTHROUGH */ + case 1: /* 1st occurrence */ + /* Locate start of replaced string. */ + re_off = match[0].rm_so + (s - ps); + /* Copy leading retained string. */ + cspace(&SS, ps, re_off, APPEND); + /* Add in regular expression. */ + regsub(&SS, s, cp->u.s->new); + /* Copy trailing retained string. */ + s += match[0].rm_eo; + slen -= match[0].rm_eo; + cspace(&SS, s, slen, APPEND); + break; + } + + /* + * Swap the substitute space and the pattern space, and make sure + * that any leftover pointers into stdio memory get lost. + */ + tspace = PS; + PS = SS; + SS = tspace; + SS.space = SS.back; + + /* Handle the 'p' flag. */ + if (cp->u.s->p) + OUT(ps) + + /* Handle the 'w' flag. */ + if (cp->u.s->wfile && !pd) { + if (cp->u.s->wfd == -1 && (cp->u.s->wfd = open(cp->u.s->wfile, + O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1) + err(FATAL, "%s: %s\n", cp->u.s->wfile, strerror(errno)); + if (write(cp->u.s->wfd, ps, psl) != psl) + err(FATAL, "%s: %s\n", cp->u.s->wfile, strerror(errno)); + } + return (1); +} + +/* + * Flush append requests. Always called before reading a line, + * therefore it also resets the substitution done (sdone) flag. + */ +static void +flush_appends() +{ + FILE *f; + int count, i; + char buf[8 * 1024]; + + for (i = 0; i < appendx; i++) + switch (appends[i].type) { + case AP_STRING: + fwrite(appends[i].s, sizeof(char), appends[i].len, + stdout); + break; + case AP_FILE: + /* + * Read files probably shouldn't be cached. Since + * it's not an error to read a non-existent file, + * it's possible that another program is interacting + * with the sed script through the file system. It + * would be truly bizarre, but possible. It's probably + * not that big a performance win, anyhow. + */ + if ((f = fopen(appends[i].s, "r")) == NULL) + break; + while (count = fread(buf, sizeof(char), sizeof(buf), f)) + (void)fwrite(buf, sizeof(char), count, stdout); + (void)fclose(f); + break; + } + if (ferror(stdout)) + err(FATAL, "stdout: %s", strerror(errno ? errno : EIO)); + appendx = sdone = 0; +} + +static void +lputs(s) + register char *s; +{ + register int count; + register char *escapes, *p; + struct winsize win; + static int termwidth = -1; + + if (termwidth == -1) + if (p = getenv("COLUMNS")) + termwidth = atoi(p); + else if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 && + win.ws_col > 0) + termwidth = win.ws_col; + else + termwidth = 60; + + for (count = 0; *s; ++s) { + if (count >= termwidth) { + (void)printf("\\\n"); + count = 0; + } + if (isascii(*s) && isprint(*s) && *s != '\\') { + (void)putchar(*s); + count++; + } else { + escapes = "\\\a\b\f\n\r\t\v"; + (void)putchar('\\'); + if (p = strchr(escapes, *s)) { + (void)putchar("\\abfnrtv"[p - escapes]); + count += 2; + } else { + (void)printf("%03o", *(u_char *)s); + count += 4; + } + } + } + (void)putchar('$'); + (void)putchar('\n'); + if (ferror(stdout)) + err(FATAL, "stdout: %s", strerror(errno ? errno : EIO)); +} + +static inline int +regexec_e(preg, string, eflags, nomatch, slen) + regex_t *preg; + const char *string; + int eflags, nomatch; + size_t slen; +{ + int eval; + + if (preg == NULL) { + if (defpreg == NULL) + err(FATAL, "first RE may not be empty"); + } else + defpreg = preg; + + /* Set anchors, discounting trailing newline (if any). */ + if (slen > 0 && string[slen - 1] == '\n') + slen--; + match[0].rm_so = 0; + match[0].rm_eo = slen; + + eval = regexec(defpreg, string, + nomatch ? 0 : maxnsub + 1, match, eflags | REG_STARTEND); + switch(eval) { + case 0: + return (1); + case REG_NOMATCH: + return (0); + } + err(FATAL, "RE error: %s", strregerror(eval, defpreg)); + /* NOTREACHED */ +} + +/* + * regsub - perform substitutions after a regexp match + * Based on a routine by Henry Spencer + */ +static void +regsub(sp, string, src) + SPACE *sp; + char *string, *src; +{ + register int len, no; + register char c, *dst; + +#define NEEDSP(reqlen) \ + if (sp->len >= sp->blen - (reqlen) - 1) { \ + sp->blen += (reqlen) + 1024; \ + sp->space = sp->back = xrealloc(sp->back, sp->blen); \ + dst = sp->space + sp->len; \ + } + + dst = sp->space + sp->len; + while ((c = *src++) != '\0') { + if (c == '&') + no = 0; + else if (c == '\\' && isdigit(*src)) + no = *src++ - '0'; + else + no = -1; + if (no < 0) { /* Ordinary character. */ + if (c == '\\' && (*src == '\\' || *src == '&')) + c = *src++; + NEEDSP(1); + *dst++ = c; + ++sp->len; + } else if (match[no].rm_so != -1 && match[no].rm_eo != -1) { + len = match[no].rm_eo - match[no].rm_so; + NEEDSP(len); + memmove(dst, string + match[no].rm_so, len); + dst += len; + sp->len += len; + } + } + NEEDSP(1); + *dst = '\0'; +} + +/* + * aspace -- + * Append the source space to the destination space, allocating new + * space as necessary. + */ +void +cspace(sp, p, len, spflag) + SPACE *sp; + char *p; + size_t len; + enum e_spflag spflag; +{ + size_t tlen; + + /* Make sure SPACE has enough memory and ramp up quickly. */ + tlen = sp->len + len + 1; + if (tlen > sp->blen) { + sp->blen = tlen + 1024; + sp->space = sp->back = xrealloc(sp->back, sp->blen); + } + + if (spflag == REPLACE) + sp->len = 0; + + memmove(sp->space + sp->len, p, len); + + sp->space[sp->len += len] = '\0'; +} + +/* + * Close all cached opened files and report any errors + */ +void +cfclose(cp, end) + register struct s_command *cp, *end; +{ + + for (; cp != end; cp = cp->next) + switch(cp->code) { + case 's': + if (cp->u.s->wfd != -1 && close(cp->u.s->wfd)) + err(FATAL, + "%s: %s", cp->u.s->wfile, strerror(errno)); + cp->u.s->wfd = -1; + break; + case 'w': + if (cp->u.fd != -1 && close(cp->u.fd)) + err(FATAL, "%s: %s", cp->t, strerror(errno)); + cp->u.fd = -1; + break; + case '{': + cfclose(cp->u.c, cp->next); + break; + } +} |