summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--src/sort.c151
1 files changed, 72 insertions, 79 deletions
diff --git a/src/sort.c b/src/sort.c
index 360b28c2f..127561e7e 100644
--- a/src/sort.c
+++ b/src/sort.c
@@ -58,10 +58,9 @@ struct rlimit { size_t rlim_cur; };
# include <langinfo.h>
#endif
-#if HAVE_PATHCONF && defined _PC_NAME_MAX
-# define NAME_MAX_IN_DIR(Dir) pathconf (Dir, _PC_NAME_MAX)
-#else
-# define NAME_MAX_IN_DIR(Dir) 255
+#ifndef SA_NOCLDSTOP
+# define sigprocmask(How, Set, Oset) /* empty */
+# define sigset_t int
#endif
#ifndef STDC_HEADERS
@@ -339,6 +338,9 @@ Set LC_ALL=C to get the traditional sort order that uses native byte values.\n\
exit (status);
}
+/* The set of signals that are caught. */
+static sigset_t caught_signals;
+
/* The list of temporary files. */
static struct tempnode
{
@@ -357,23 +359,46 @@ cleanup (void)
unlink (node->name);
}
-static FILE *
-xtmpfopen (const char *file)
+/* Create a new temporary file, returning its newly allocated name.
+ Store into *PFP a stream open for writing. */
+
+static char *
+create_temp_file (FILE **pfp)
{
- FILE *fp;
+ static char const slashbase[] = "/sortXXXXXX";
+ static size_t temp_dir_index;
+ sigset_t oldset;
int fd;
+ int saved_errno;
+ char const *temp_dir = temp_dirs[temp_dir_index];
+ size_t len = strlen (temp_dir);
+ char *file = xmalloc (len + sizeof slashbase);
+ struct tempnode *node = (struct tempnode *) xmalloc (sizeof *node);
- /* Open temporary file exclusively, to foil a common
- denial-of-service attack. */
- fd = open (file, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0600);
- if (fd < 0 || (fp = fdopen (fd, "w")) == NULL)
+ memcpy (file, temp_dir, len);
+ memcpy (file + len, slashbase, sizeof slashbase);
+ node->name = file;
+ node->next = temphead.next;
+ if (++temp_dir_index == temp_dir_count)
+ temp_dir_index = 0;
+
+ /* Create the temporary file in a critical section, to avoid races. */
+ sigprocmask (SIG_BLOCK, &caught_signals, &oldset);
+ fd = mkstemp (file);
+ if (0 <= fd)
+ temphead.next = node;
+ saved_errno = errno;
+ sigprocmask (SIG_SETMASK, &oldset, NULL);
+ errno = saved_errno;
+
+ if (fd < 0 || (*pfp = fdopen (fd, "w")) == NULL)
{
error (0, errno, "%s", file);
cleanup ();
exit (SORT_FAILURE);
}
- return fp;
+ return file;
}
static FILE *
@@ -453,41 +478,6 @@ add_temp_dir (char const *dir)
temp_dirs[temp_dir_count++] = dir;
}
-/* Return a name for a temporary file. */
-
-static char *
-tempname (void)
-{
- static unsigned long sequence_number;
-
- unsigned long seq = sequence_number++;
- unsigned long pid = process_id;
- char const *temp_dir = temp_dirs[seq % temp_dir_count];
- size_t len = strlen (temp_dir);
- char const *slash = "/" + (len == 0 || temp_dir[len - 1] == '/');
- char *name = xmalloc (len + 1 + sizeof "sort" - 1
- + sizeof pid * CHAR_BIT / 3 + 1
- + sizeof seq * CHAR_BIT / 3 + 1);
- int long_file_names = NAME_MAX_IN_DIR (temp_dir) > 12;
- struct tempnode *node;
-
- if (long_file_names)
- sprintf (name, "%s%ssort%lu.%.5lu", temp_dir, slash, pid, seq);
- else
- {
- /* Make sure the file name is safe for an 8.3 filesystem. */
- sprintf (name, "%s%ss%.5d%.2d.%.3d", temp_dir, slash,
- (int) (pid % 100000), (int) (seq / 1000 % 100),
- (int) (seq % 1000));
- }
-
- node = (struct tempnode *) xmalloc (sizeof (struct tempnode));
- node->name = name;
- node->next = temphead.next;
- temphead.next = node;
- return name;
-}
-
/* Search through the list of temporary files for NAME;
remove it if it is found on the list. */
@@ -1817,14 +1807,14 @@ merge (char **files, int nfiles, FILE *ofp, const char *output_file)
{
for (j = 0; j < NMERGE; ++j)
fps[j] = xfopen (files[i * NMERGE + j], "r");
- tfp = xtmpfopen (temp = tempname ());
+ temp = create_temp_file (&tfp);
mergefps (fps, &files[i * NMERGE], NMERGE, tfp, temp);
xfclose (tfp);
files[t++] = temp;
}
for (j = 0; j < nfiles % NMERGE; ++j)
fps[j] = xfopen (files[i * NMERGE + j], "r");
- tfp = xtmpfopen (temp = tempname ());
+ temp = create_temp_file (&tfp);
mergefps (fps, &files[i * NMERGE], nfiles % NMERGE, tfp, temp);
xfclose (tfp);
files[t++] = temp;
@@ -1891,7 +1881,7 @@ sort (char **files, int nfiles, FILE *ofp, const char *output_file)
else
{
++n_temp_files;
- tfp = xtmpfopen (temp_output = tempname ());
+ temp_output = create_temp_file (&tfp);
}
do
@@ -1980,17 +1970,25 @@ parse_field_count (char const *string, size_t *val)
static void
sighandler (int sig)
{
+#ifndef SA_NOCLDSTOP
+ signal (sig, SIG_IGN);
+#endif
+
+ cleanup ();
+
#ifdef SA_NOCLDSTOP
- struct sigaction sigact;
+ {
+ struct sigaction sigact;
- sigact.sa_handler = SIG_DFL;
- sigemptyset (&sigact.sa_mask);
- sigact.sa_flags = 0;
- sigaction (sig, &sigact, NULL);
+ sigact.sa_handler = SIG_DFL;
+ sigemptyset (&sigact.sa_mask);
+ sigact.sa_flags = 0;
+ sigaction (sig, &sigact, NULL);
+ }
#else
signal (sig, SIG_DFL);
#endif
- cleanup ();
+
kill (process_id, sig);
}
@@ -2059,6 +2057,8 @@ main (int argc, char **argv)
char *minus = "-", **files, *tmp;
char const *outfile = minus;
FILE *ofp;
+ static int const sigs[] = { SIGHUP, SIGINT, SIGPIPE, SIGTERM };
+ int nsigs = sizeof sigs / sizeof *sigs;
#ifdef SA_NOCLDSTOP
struct sigaction oldact, newact;
#endif
@@ -2109,32 +2109,26 @@ main (int argc, char **argv)
xalloc_fail_func = cleanup;
#ifdef SA_NOCLDSTOP
+ sigemptyset (&caught_signals);
+ for (i = 0; i < nsigs; i++)
+ sigaddset (&caught_signals, sigs[i]);
newact.sa_handler = sighandler;
- sigemptyset (&newact.sa_mask);
+ newact.sa_mask = caught_signals;
newact.sa_flags = 0;
+#endif
- sigaction (SIGINT, NULL, &oldact);
- if (oldact.sa_handler != SIG_IGN)
- sigaction (SIGINT, &newact, NULL);
- sigaction (SIGHUP, NULL, &oldact);
- if (oldact.sa_handler != SIG_IGN)
- sigaction (SIGHUP, &newact, NULL);
- sigaction (SIGPIPE, NULL, &oldact);
- if (oldact.sa_handler != SIG_IGN)
- sigaction (SIGPIPE, &newact, NULL);
- sigaction (SIGTERM, NULL, &oldact);
- if (oldact.sa_handler != SIG_IGN)
- sigaction (SIGTERM, &newact, NULL);
+ for (i = 0; i < nsigs; i++)
+ {
+ int sig = sigs[i];
+#ifdef SA_NOCLDSTOP
+ sigaction (sig, NULL, &oldact);
+ if (oldact.sa_handler != SIG_IGN)
+ sigaction (sig, &newact, NULL);
#else
- if (signal (SIGINT, SIG_IGN) != SIG_IGN)
- signal (SIGINT, sighandler);
- if (signal (SIGHUP, SIG_IGN) != SIG_IGN)
- signal (SIGHUP, sighandler);
- if (signal (SIGPIPE, SIG_IGN) != SIG_IGN)
- signal (SIGPIPE, sighandler);
- if (signal (SIGTERM, SIG_IGN) != SIG_IGN)
- signal (SIGTERM, sighandler);
+ if (signal (sig, SIG_IGN) != SIG_IGN)
+ signal (sig, sighandler);
#endif
+ }
gkey.sword = gkey.eword = -1;
gkey.ignore = NULL;
@@ -2466,8 +2460,7 @@ but lacks following character offset"));
}
in_fp = xfopen (files[i], "r");
- tmp = tempname ();
- out_fp = xtmpfopen (tmp);
+ tmp = create_temp_file (&out_fp);
/* FIXME: maybe use copy.c(copy) here. */
while ((cc = fread (buf, 1, sizeof buf, in_fp)) > 0)
write_bytes (buf, cc, out_fp, tmp);
generated by cgit v1.2.3-70-g09d2 (git 2.47.0) at 2024-10-31 01:21:40 +0000