freebsd-dev/usr.bin/m4/gnum4.c
Marcelo Araujo 1b56693f8b Use NULL instead of 0 for pointers.
fopen(3) will return NULL in case it cannot open the STREAM.

MFC after:	2 weeks.
2016-04-18 07:09:34 +00:00

674 lines
14 KiB
C

/* $OpenBSD: gnum4.c,v 1.50 2015/04/29 00:13:26 millert Exp $ */
/*
* 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 <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);
}
static void
add_sub(int n, const char *string, regex_t *re, regmatch_t *pm)
{
if (n > (int)re->re_nsub)
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) {
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) {
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 pid, 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 ((pid = wait(&status)) != cpid && pid >= 0)
continue;
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);
}