/*
* subst.c --- substitution program
*
- * Subst is used as a quicky program to do @ substitutions
- *
+ * Subst is used as a quickie program to do @ substitutions
+ *
*/
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#else
+#define HAVE_SYS_TIME_H
+#endif
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
+#endif
+#include <fcntl.h>
#include <time.h>
#include <utime.h>
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
#ifdef HAVE_GETOPT_H
#include <getopt.h>
struct subst_entry *next;
};
-struct subst_entry *subst_table = 0;
+static struct subst_entry *subst_table = 0;
static int add_subst(char *name, char *value)
{
struct subst_entry *ent = 0;
- int retval;
-
- retval = ENOMEM;
+
ent = (struct subst_entry *) malloc(sizeof(struct subst_entry));
if (!ent)
goto fail;
return 0;
fail:
if (ent) {
- if (ent->name)
- free(ent->name);
- if (ent->value)
- free(ent->value);
+ free(ent->name);
free(ent);
}
- return retval;
+ return ENOMEM;
}
static struct subst_entry *fetch_subst_entry(char *name)
return NULL;
memcpy(start, begin, len);
start[len] = 0;
-
+
/*
* The substitution variable must all be in the of [0-9A-Za-z_].
* If it isn't, this must be an invalid symbol name.
}
ent = fetch_subst_entry(replace_name);
if (!ent) {
- fprintf(stderr, "Unfound expansion: '%s'\n",
+ fprintf(stderr, "Unfound expansion: '%s'\n",
replace_name);
ptr = end_ptr + 1;
continue;
#endif
ptr = name_ptr-1;
replace_string(ptr, end_ptr, ent->value);
+ if ((ent->value[0] == '@') &&
+ (strlen(replace_name) == strlen(ent->value)-2) &&
+ !strncmp(replace_name, ent->value+1,
+ strlen(ent->value)-2))
+ /* avoid an infinite loop */
+ ptr += strlen(ent->value);
}
/*
* Now do a second pass to expand ${FOO}
if (!replace_name) {
ptr = name_ptr;
continue;
- }
+ }
ent = fetch_subst_entry(replace_name);
if (!ent) {
ptr = end_ptr + 1;
/*
* Return 0 if the files are different, 1 if the files are the same.
*/
-static int compare_file(const char *outfn, const char *newfn)
+static int compare_file(FILE *old_f, FILE *new_f)
{
- FILE *old_f, *new_f;
char oldbuf[2048], newbuf[2048], *oldcp, *newcp;
int retval;
- old_f = fopen(outfn, "r");
- if (!old_f)
- return 0;
- new_f = fopen(newfn, "r");
- if (!new_f)
- return 0;
-
while (1) {
oldcp = fgets(oldbuf, sizeof(oldbuf), old_f);
newcp = fgets(newbuf, sizeof(newbuf), new_f);
break;
}
}
- fclose(old_f);
- fclose(new_f);
return retval;
}
+void set_utimes(const char *filename, int fd, const struct timeval times[2])
+{
+#ifdef HAVE_FUTIMES
+ if (futimes(fd, times) < 0)
+ perror("futimes");
+#elif HAVE_UTIMES
+ if (utimes(filename, times) < 0)
+ perror("utimes");
+#else
+ struct utimbuf ut;
+
+ ut.actime = times[0].tv_sec;
+ ut.modtime = times[1].tv_sec;
+ if (utime(filename, &ut) < 0)
+ perror("utime");
+#endif
+}
int main(int argc, char **argv)
{
char line[2048];
int c;
- FILE *in, *out;
+ int fd, ofd = -1;
+ FILE *in, *out, *old = NULL;
char *outfn = NULL, *newfn = NULL;
int verbose = 0;
int adjust_timestamp = 0;
+ int got_atime = 0;
struct stat stbuf;
- struct utimbuf ut;
-
+ struct timeval tv[2];
+
while ((c = getopt (argc, argv, "f:tv")) != EOF) {
switch (c) {
case 'f':
verbose++;
break;
default:
- fprintf(stderr, "%s: [-f config-file] [file]\n",
+ fprintf(stderr, "%s: [-f config-file] [file]\n",
argv[0]);
break;
}
optind++;
} else
in = stdin;
-
+
if (optind < argc) {
outfn = argv[optind];
newfn = (char *) malloc(strlen(outfn)+20);
}
strcpy(newfn, outfn);
strcat(newfn, ".new");
- out = fopen(newfn, "w");
- if (!out) {
+ ofd = open(newfn, O_CREAT|O_TRUNC|O_RDWR, 0644);
+ if (ofd < 0) {
perror(newfn);
exit(1);
}
+ out = fdopen(ofd, "w+");
+ if (!out) {
+ perror("fdopen");
+ exit(1);
+ }
+
+ fd = open(outfn, O_RDONLY);
+ if (fd > 0) {
+ /* save the original atime, if possible */
+ if (fstat(fd, &stbuf) == 0) {
+#if HAVE_STRUCT_STAT_ST_ATIM
+ tv[0].tv_sec = stbuf.st_atim.tv_sec;
+ tv[0].tv_usec = stbuf.st_atim.tv_nsec / 1000;
+#else
+ tv[0].tv_sec = stbuf.st_atime;
+ tv[0].tv_usec = 0;
+#endif
+ got_atime = 1;
+ }
+ old = fdopen(fd, "r");
+ if (!old)
+ close(fd);
+ }
} else {
out = stdout;
outfn = 0;
}
-
+
while (!feof(in)) {
if (fgets(line, sizeof(line), in) == NULL)
break;
fputs(line, out);
}
fclose(in);
- fclose(out);
if (outfn) {
- struct stat st;
- if (compare_file(outfn, newfn)) {
+ fflush(out);
+ rewind(out);
+ if (old && compare_file(old, out)) {
if (verbose)
printf("No change, keeping %s.\n", outfn);
if (adjust_timestamp) {
- if (stat(outfn, &stbuf) == 0) {
- if (verbose)
- printf("Updating modtime for %s\n", outfn);
- ut.actime = stbuf.st_atime;
- ut.modtime = time(0);
- if (utime(outfn, &ut) < 0)
- perror("utime");
+ if (verbose)
+ printf("Updating modtime for %s\n", outfn);
+ if (gettimeofday(&tv[1], NULL) < 0) {
+ perror("gettimeofday");
+ exit(1);
}
+ if (got_atime == 0)
+ tv[0] = tv[1];
+ else if (verbose)
+ printf("Using original atime\n");
+ set_utimes(outfn, fileno(old), tv);
}
- unlink(newfn);
+ if (ofd >= 0)
+ (void) fchmod(ofd, 0444);
+ fclose(out);
+ if (unlink(newfn) < 0)
+ perror("unlink");
} else {
if (verbose)
printf("Creating or replacing %s.\n", outfn);
- rename(newfn, outfn);
+ if (ofd >= 0)
+ (void) fchmod(ofd, 0444);
+ fclose(out);
+ if (old)
+ fclose(old);
+ old = NULL;
+ if (rename(newfn, outfn) < 0) {
+ perror("rename");
+ exit(1);
+ }
}
- /* set read-only to alert user it is a generated file */
- if (stat(outfn, &st) == 0)
- chmod(outfn, st.st_mode & ~0222);
}
+ if (old)
+ fclose(old);
+ if (newfn)
+ free(newfn);
return (0);
}