/usr.bin/m4/gnum4.c
C | 696 lines | 558 code | 69 blank | 69 comment | 150 complexity | 39009be0673bd6beaf2c7c219e3b97f0 MD5 | raw file
- /* $OpenBSD: gnum4.c,v 1.52 2017/08/21 21:41:13 deraadt Exp $ */
- /*-
- * SPDX-License-Identifier: BSD-2-Clause
- *
- * Copyright (c) 1999 Marc Espie
- *
- * 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.
- *
- * 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.
- */
- #include <sys/cdefs.h>
- __FBSDID("$FreeBSD$");
- /*
- * functions needed to support gnu-m4 extensions, including a fake freezing
- */
- #include <sys/types.h>
- #include <sys/wait.h>
- #include <ctype.h>
- #include <err.h>
- #include <paths.h>
- #include <regex.h>
- #include <stdarg.h>
- #include <stddef.h>
- #include <stdlib.h>
- #include <stdint.h>
- #include <stdio.h>
- #include <string.h>
- #include <errno.h>
- #include <unistd.h>
- #include <limits.h>
- #include "mdef.h"
- #include "stdd.h"
- #include "extern.h"
- int mimic_gnu = 0;
- /*
- * Support for include path search
- * First search in the current directory.
- * If not found, and the path is not absolute, include path kicks in.
- * First, -I options, in the order found on the command line.
- * Then M4PATH env variable
- */
- static struct path_entry {
- char *name;
- struct path_entry *next;
- } *first, *last;
- static struct path_entry *new_path_entry(const char *);
- static void ensure_m4path(void);
- static struct input_file *dopath(struct input_file *, const char *);
- static struct path_entry *
- new_path_entry(const char *dirname)
- {
- struct path_entry *n;
- n = malloc(sizeof(struct path_entry));
- if (!n)
- errx(1, "out of memory");
- n->name = xstrdup(dirname);
- n->next = 0;
- return n;
- }
- void
- addtoincludepath(const char *dirname)
- {
- struct path_entry *n;
- n = new_path_entry(dirname);
- if (last) {
- last->next = n;
- last = n;
- }
- else
- last = first = n;
- }
- static void
- ensure_m4path(void)
- {
- static int envpathdone = 0;
- char *envpath;
- char *sweep;
- char *path;
- if (envpathdone)
- return;
- envpathdone = TRUE;
- envpath = getenv("M4PATH");
- if (!envpath)
- return;
- /* for portability: getenv result is read-only */
- envpath = xstrdup(envpath);
- for (sweep = envpath;
- (path = strsep(&sweep, ":")) != NULL;)
- addtoincludepath(path);
- free(envpath);
- }
- static
- struct input_file *
- dopath(struct input_file *i, const char *filename)
- {
- char path[PATH_MAX];
- struct path_entry *pe;
- FILE *f;
- for (pe = first; pe; pe = pe->next) {
- snprintf(path, sizeof(path), "%s/%s", pe->name, filename);
- if ((f = fopen(path, "r")) != NULL) {
- set_input(i, f, path);
- return i;
- }
- }
- return NULL;
- }
- struct input_file *
- fopen_trypath(struct input_file *i, const char *filename)
- {
- FILE *f;
- f = fopen(filename, "r");
- if (f != NULL) {
- set_input(i, f, filename);
- return i;
- }
- if (filename[0] == '/')
- return NULL;
- ensure_m4path();
- return dopath(i, filename);
- }
- void
- doindir(const char *argv[], int argc)
- {
- ndptr n;
- struct macro_definition *p = NULL;
- n = lookup(argv[2]);
- if (n == NULL || (p = macro_getdef(n)) == NULL)
- m4errx(1, "indir: undefined macro %s.", argv[2]);
- argv[1] = p->defn;
- eval(argv+1, argc-1, p->type, is_traced(n));
- }
- void
- dobuiltin(const char *argv[], int argc)
- {
- ndptr p;
- argv[1] = NULL;
- p = macro_getbuiltin(argv[2]);
- if (p != NULL)
- eval(argv+1, argc-1, macro_builtin_type(p), is_traced(p));
- else
- m4errx(1, "unknown builtin %s.", argv[2]);
- }
- /* We need some temporary buffer space, as pb pushes BACK and substitution
- * proceeds forward... */
- static char *buffer;
- static size_t bufsize = 0;
- static size_t current = 0;
- static void addchars(const char *, size_t);
- static void addchar(int);
- static char *twiddle(const char *);
- static char *getstring(void);
- static void exit_regerror(int, regex_t *, const char *);
- static void do_subst(const char *, regex_t *, const char *, const char *,
- regmatch_t *);
- static void do_regexpindex(const char *, regex_t *, const char *, regmatch_t *);
- static void do_regexp(const char *, regex_t *, const char *, const char *,
- regmatch_t *);
- static void add_sub(int, const char *, regex_t *, regmatch_t *);
- static void add_replace(const char *, regex_t *, const char *, regmatch_t *);
- #define addconstantstring(s) addchars((s), sizeof(s)-1)
- static void
- addchars(const char *c, size_t n)
- {
- if (n == 0)
- return;
- while (current + n > bufsize) {
- if (bufsize == 0)
- bufsize = 1024;
- else if (bufsize <= SIZE_MAX/2) {
- bufsize *= 2;
- } else {
- errx(1, "size overflow");
- }
- buffer = xrealloc(buffer, bufsize, NULL);
- }
- memcpy(buffer+current, c, n);
- current += n;
- }
- static void
- addchar(int c)
- {
- if (current +1 > bufsize) {
- if (bufsize == 0)
- bufsize = 1024;
- else
- bufsize *= 2;
- buffer = xrealloc(buffer, bufsize, NULL);
- }
- buffer[current++] = c;
- }
- static char *
- getstring(void)
- {
- addchar('\0');
- current = 0;
- return buffer;
- }
- static void
- exit_regerror(int er, regex_t *re, const char *source)
- {
- size_t errlen;
- char *errbuf;
- errlen = regerror(er, re, NULL, 0);
- errbuf = xalloc(errlen,
- "malloc in regerror: %lu", (unsigned long)errlen);
- regerror(er, re, errbuf, errlen);
- m4errx(1, "regular expression error in %s: %s.", source, errbuf);
- }
- /* warnx() plus check to see if we need to change exit code or exit .
- * -E flag functionality.
- */
- void
- m4_warnx(const char *fmt, ...)
- {
- va_list ap;
- va_start(ap, fmt);
- warnx(fmt, ap);
- va_end(ap);
- if (fatal_warns)
- exit(1);
- if (error_warns)
- exit_code = 1;
- }
- static void
- add_sub(int n, const char *string, regex_t *re, regmatch_t *pm)
- {
- if (n > (int)re->re_nsub)
- m4_warnx("No subexpression %d", n);
- /* Subexpressions that did not match are
- * not an error. */
- else if (pm[n].rm_so != -1 &&
- pm[n].rm_eo != -1) {
- addchars(string + pm[n].rm_so,
- pm[n].rm_eo - pm[n].rm_so);
- }
- }
- /* Add replacement string to the output buffer, recognizing special
- * constructs and replacing them with substrings of the original string.
- */
- static void
- add_replace(const char *string, regex_t *re, const char *replace, regmatch_t *pm)
- {
- const char *p;
- for (p = replace; *p != '\0'; p++) {
- if (*p == '&' && !mimic_gnu) {
- add_sub(0, string, re, pm);
- continue;
- }
- if (*p == '\\') {
- if (p[1] == '\\') {
- addchar(p[1]);
- p++;
- continue;
- }
- if (p[1] == '&') {
- if (mimic_gnu)
- add_sub(0, string, re, pm);
- else
- addchar(p[1]);
- p++;
- continue;
- }
- if (isdigit((unsigned char)p[1])) {
- add_sub(*(++p) - '0', string, re, pm);
- continue;
- }
- }
- addchar(*p);
- }
- }
- static void
- do_subst(const char *string, regex_t *re, const char *source,
- const char *replace, regmatch_t *pm)
- {
- int error;
- int flags = 0;
- const char *last_match = NULL;
- while ((error = regexec(re, string, re->re_nsub+1, pm, flags)) == 0) {
- if (pm[0].rm_eo != 0) {
- if (string[pm[0].rm_eo-1] == '\n')
- flags = 0;
- else
- flags = REG_NOTBOL;
- }
- /* NULL length matches are special... We use the `vi-mode'
- * rule: don't allow a NULL-match at the last match
- * position.
- */
- if (pm[0].rm_so == pm[0].rm_eo &&
- string + pm[0].rm_so == last_match) {
- if (*string == '\0')
- return;
- addchar(*string);
- if (*string++ == '\n')
- flags = 0;
- else
- flags = REG_NOTBOL;
- continue;
- }
- last_match = string + pm[0].rm_so;
- addchars(string, pm[0].rm_so);
- add_replace(string, re, replace, pm);
- string += pm[0].rm_eo;
- }
- if (error != REG_NOMATCH)
- exit_regerror(error, re, source);
- pbstr(string);
- }
- static void
- do_regexp(const char *string, regex_t *re, const char *source,
- const char *replace, regmatch_t *pm)
- {
- int error;
- switch(error = regexec(re, string, re->re_nsub+1, pm, 0)) {
- case 0:
- add_replace(string, re, replace, pm);
- pbstr(getstring());
- break;
- case REG_NOMATCH:
- break;
- default:
- exit_regerror(error, re, source);
- }
- }
- static void
- do_regexpindex(const char *string, regex_t *re, const char *source,
- regmatch_t *pm)
- {
- int error;
- switch(error = regexec(re, string, re->re_nsub+1, pm, 0)) {
- case 0:
- pbunsigned(pm[0].rm_so);
- break;
- case REG_NOMATCH:
- pbnum(-1);
- break;
- default:
- exit_regerror(error, re, source);
- }
- }
- /* In Gnu m4 mode, parentheses for backmatch don't work like POSIX 1003.2
- * says. So we twiddle with the regexp before passing it to regcomp.
- */
- static char *
- twiddle(const char *p)
- {
- /* + at start of regexp is a normal character for Gnu m4 */
- if (*p == '^') {
- addchar(*p);
- p++;
- }
- if (*p == '+') {
- addchar('\\');
- }
- /* This could use strcspn for speed... */
- while (*p != '\0') {
- if (*p == '\\') {
- switch(p[1]) {
- case '(':
- case ')':
- case '|':
- addchar(p[1]);
- break;
- case 'w':
- addconstantstring("[_a-zA-Z0-9]");
- break;
- case 'W':
- addconstantstring("[^_a-zA-Z0-9]");
- break;
- case '<':
- addconstantstring("[[:<:]]");
- break;
- case '>':
- addconstantstring("[[:>:]]");
- break;
- default:
- addchars(p, 2);
- break;
- }
- p+=2;
- continue;
- }
- if (*p == '(' || *p == ')' || *p == '|')
- addchar('\\');
- addchar(*p);
- p++;
- }
- return getstring();
- }
- /* patsubst(string, regexp, opt replacement) */
- /* argv[2]: string
- * argv[3]: regexp
- * argv[4]: opt rep
- */
- void
- dopatsubst(const char *argv[], int argc)
- {
- if (argc <= 3) {
- m4_warnx("Too few arguments to patsubst");
- return;
- }
- /* special case: empty regexp */
- if (argv[3][0] == '\0') {
- const char *s;
- size_t len;
- if (argc > 4 && argv[4])
- len = strlen(argv[4]);
- else
- len = 0;
- for (s = argv[2]; *s != '\0'; s++) {
- addchars(argv[4], len);
- addchar(*s);
- }
- } else {
- int error;
- regex_t re;
- regmatch_t *pmatch;
- int mode = REG_EXTENDED;
- const char *source;
- size_t l = strlen(argv[3]);
- if (!mimic_gnu ||
- (argv[3][0] == '^') ||
- (l > 0 && argv[3][l-1] == '$'))
- mode |= REG_NEWLINE;
- source = mimic_gnu ? twiddle(argv[3]) : argv[3];
- error = regcomp(&re, source, mode);
- if (error != 0)
- exit_regerror(error, &re, source);
- pmatch = xreallocarray(NULL, re.re_nsub+1, sizeof(regmatch_t),
- NULL);
- do_subst(argv[2], &re, source,
- argc > 4 && argv[4] != NULL ? argv[4] : "", pmatch);
- free(pmatch);
- regfree(&re);
- }
- pbstr(getstring());
- }
- void
- doregexp(const char *argv[], int argc)
- {
- int error;
- regex_t re;
- regmatch_t *pmatch;
- const char *source;
- if (argc <= 3) {
- m4_warnx("Too few arguments to regexp");
- return;
- }
- /* special gnu case */
- if (argv[3][0] == '\0' && mimic_gnu) {
- if (argc == 4 || argv[4] == NULL)
- return;
- else
- pbstr(argv[4]);
- }
- source = mimic_gnu ? twiddle(argv[3]) : argv[3];
- error = regcomp(&re, source, REG_EXTENDED|REG_NEWLINE);
- if (error != 0)
- exit_regerror(error, &re, source);
- pmatch = xreallocarray(NULL, re.re_nsub+1, sizeof(regmatch_t), NULL);
- if (argc == 4 || argv[4] == NULL)
- do_regexpindex(argv[2], &re, source, pmatch);
- else
- do_regexp(argv[2], &re, source, argv[4], pmatch);
- free(pmatch);
- regfree(&re);
- }
- void
- doformat(const char *argv[], int argc)
- {
- const char *format = argv[2];
- int pos = 3;
- int left_padded;
- long width;
- size_t l;
- const char *thisarg = NULL;
- char temp[2];
- long extra;
- while (*format != 0) {
- if (*format != '%') {
- addchar(*format++);
- continue;
- }
- format++;
- if (*format == '%') {
- addchar(*format++);
- continue;
- }
- if (*format == 0) {
- addchar('%');
- break;
- }
- if (*format == '*') {
- format++;
- if (pos >= argc)
- m4errx(1,
- "Format with too many format specifiers.");
- width = strtol(argv[pos++], NULL, 10);
- } else {
- width = strtol(format, __DECONST(char **,&format), 10);
- }
- if (width < 0) {
- left_padded = 1;
- width = -width;
- } else {
- left_padded = 0;
- }
- if (*format == '.') {
- format++;
- if (*format == '*') {
- format++;
- if (pos >= argc)
- m4errx(1,
- "Format with too many format specifiers.");
- extra = strtol(argv[pos++], NULL, 10);
- } else {
- extra = strtol(format, __DECONST(char **, &format), 10);
- }
- } else {
- extra = LONG_MAX;
- }
- if (pos >= argc)
- m4errx(1, "Format with too many format specifiers.");
- switch(*format) {
- case 's':
- thisarg = argv[pos++];
- break;
- case 'c':
- temp[0] = strtoul(argv[pos++], NULL, 10);
- temp[1] = 0;
- thisarg = temp;
- break;
- default:
- m4errx(1, "Unsupported format specification: %s.",
- argv[2]);
- }
- format++;
- l = strlen(thisarg);
- if ((long)l > extra)
- l = extra;
- if (!left_padded) {
- while ((long)l < width--)
- addchar(' ');
- }
- addchars(thisarg, l);
- if (left_padded) {
- while ((long)l < width--)
- addchar(' ');
- }
- }
- pbstr(getstring());
- }
- void
- doesyscmd(const char *cmd)
- {
- int p[2];
- pid_t cpid;
- char *argv[4];
- int cc;
- int status;
- /* Follow gnu m4 documentation: first flush buffers. */
- fflush(NULL);
- argv[0] = __DECONST(char *, "sh");
- argv[1] = __DECONST(char *, "-c");
- argv[2] = __DECONST(char *, cmd);
- argv[3] = NULL;
- /* Just set up standard output, share stderr and stdin with m4 */
- if (pipe(p) == -1)
- err(1, "bad pipe");
- switch(cpid = fork()) {
- case -1:
- err(1, "bad fork");
- /* NOTREACHED */
- case 0:
- (void) close(p[0]);
- (void) dup2(p[1], 1);
- (void) close(p[1]);
- execv(_PATH_BSHELL, argv);
- exit(1);
- default:
- /* Read result in two stages, since m4's buffer is
- * pushback-only. */
- (void) close(p[1]);
- do {
- char result[BUFSIZE];
- cc = read(p[0], result, sizeof result);
- if (cc > 0)
- addchars(result, cc);
- } while (cc > 0 || (cc == -1 && errno == EINTR));
- (void) close(p[0]);
- while (waitpid(cpid, &status, 0) == -1) {
- if (errno != EINTR)
- break;
- }
- pbstr(getstring());
- }
- }
- void
- getdivfile(const char *name)
- {
- FILE *f;
- int c;
- f = fopen(name, "r");
- if (!f)
- return;
- while ((c = getc(f))!= EOF)
- putc(c, active);
- (void) fclose(f);
- }