/* update-game-score.c --- Update a score file
-Copyright (C) 2002-2013 Free Software Foundation, Inc.
+Copyright (C) 2002-2014 Free Software Foundation, Inc.
Author: Colin Walters <walters@debian.org>
#include <unistd.h>
#include <errno.h>
+#include <inttypes.h>
#include <limits.h>
+#include <stdbool.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/stat.h>
#include <getopt.h>
-#define MAX_ATTEMPTS 5
-#define MAX_SCORES 200
-#define MAX_DATA_LEN 1024
+#ifdef WINDOWSNT
+#include "ntlib.h"
+#endif
-#ifndef HAVE_DIFFTIME
-/* OK on POSIX (time_t is arithmetic type) modulo overflow in subtraction. */
-#define difftime(t1, t0) (double)((t1) - (t0))
+#ifndef min
+# define min(a,b) ((a) < (b) ? (a) : (b))
#endif
+#define MAX_ATTEMPTS 5
+#define MAX_DATA_LEN 1024
+
static _Noreturn void
usage (int err)
{
struct score_entry
{
- long score;
- char *username;
- char *data;
+ char *score;
+ char *user_data;
};
+#define MAX_SCORES min (PTRDIFF_MAX, SIZE_MAX / sizeof (struct score_entry))
+
static int read_scores (const char *filename, struct score_entry **scores,
- int *count);
-static int push_score (struct score_entry **scores, int *count,
- int newscore, char *username, char *newdata);
-static void sort_scores (struct score_entry *scores, int count, int reverse);
+ ptrdiff_t *count, ptrdiff_t *alloc);
+static int push_score (struct score_entry **scores, ptrdiff_t *count,
+ ptrdiff_t *size, struct score_entry const *newscore);
+static void sort_scores (struct score_entry *scores, ptrdiff_t count,
+ bool reverse);
static int write_scores (const char *filename,
- const struct score_entry *scores, int count);
+ const struct score_entry *scores, ptrdiff_t count);
static _Noreturn void
lose (const char *msg)
static _Noreturn void
lose_syserr (const char *msg)
{
- fprintf (stderr, "%s: %s\n", msg, strerror (errno));
+ fprintf (stderr, "%s: %s\n", msg,
+ errno ? strerror (errno) : "Invalid data in score file");
exit (EXIT_FAILURE);
}
get_user_id (void)
{
struct passwd *buf = getpwuid (getuid ());
- if (!buf)
+ if (!buf || strchr (buf->pw_name, ' ') || strchr (buf->pw_name, '\n'))
{
- long uid = getuid ();
- char *name = malloc (sizeof uid * CHAR_BIT / 3 + 1);
+ intmax_t uid = getuid ();
+ char *name = malloc (sizeof uid * CHAR_BIT / 3 + 4);
if (name)
- sprintf (name, "%ld", uid);
+ sprintf (name, "%"PRIdMAX, uid);
return name;
}
return buf->pw_name;
}
static const char *
-get_prefix (int running_suid, const char *user_prefix)
+get_prefix (bool running_suid, const char *user_prefix)
{
if (!running_suid && user_prefix == NULL)
lose ("Not using a shared game directory, and no prefix given.");
return user_prefix;
}
+static char *
+normalize_integer (char *num)
+{
+ bool neg;
+ char *p;
+ while (*num != '\n' && isspace (*num))
+ num++;
+ neg = *num == '-';
+ num += neg || *num == '-';
+
+ if (*num == '0')
+ {
+ while (*++num == '0')
+ continue;
+ neg &= !!*num;
+ num -= !*num;
+ }
+
+ for (p = num; '0' <= *p && *p <= '9'; p++)
+ continue;
+
+ if (*p || p == num)
+ {
+ errno = 0;
+ return 0;
+ }
+
+ if (neg)
+ *--num = '-';
+ return num;
+}
+
int
main (int argc, char **argv)
{
- int c, running_suid;
+ int c;
+ bool running_suid;
void *lockstate;
- char *user_id, *scorefile;
+ char *scorefile;
+ char *end, *nl, *user, *data;
const char *prefix, *user_prefix = NULL;
- struct stat buf;
struct score_entry *scores;
- int newscore, scorecount, reverse = 0, max = MAX_SCORES;
- char *newdata;
+ struct score_entry newscore;
+ bool reverse = false;
+ ptrdiff_t scorecount, scorealloc;
+ ptrdiff_t max_scores = MAX_SCORES;
srand (time (0));
reverse = 1;
break;
case 'm':
- max = atoi (optarg);
- if (max > MAX_SCORES)
- max = MAX_SCORES;
+ {
+ intmax_t m = strtoimax (optarg, &end, 10);
+ if (optarg == end || *end || m < 0)
+ usage (EXIT_FAILURE);
+ max_scores = min (m, MAX_SCORES);
+ }
break;
default:
usage (EXIT_FAILURE);
}
- if (optind+3 != argc)
+ if (argc - optind != 3)
usage (EXIT_FAILURE);
running_suid = (getuid () != geteuid ());
strcpy (scorefile, prefix);
strcat (scorefile, "/");
strcat (scorefile, argv[optind]);
- newscore = atoi (argv[optind+1]);
- newdata = argv[optind+2];
- if (strlen (newdata) > MAX_DATA_LEN)
- newdata[MAX_DATA_LEN] = '\0';
- user_id = get_user_id ();
- if (user_id == NULL)
- lose_syserr ("Couldn't determine user id");
+ newscore.score = normalize_integer (argv[optind + 1]);
+ if (! newscore.score)
+ {
+ fprintf (stderr, "%s: Invalid score\n", argv[optind + 1]);
+ return EXIT_FAILURE;
+ }
- if (stat (scorefile, &buf) < 0)
- lose_syserr ("Failed to access scores file");
+ user = get_user_id ();
+ if (! user)
+ lose_syserr ("Couldn't determine user id");
+ data = argv[optind + 2];
+ if (strlen (data) > MAX_DATA_LEN)
+ data[MAX_DATA_LEN] = '\0';
+ nl = strchr (data, '\n');
+ if (nl)
+ *nl = '\0';
+ newscore.user_data = malloc (strlen (user) + 1 + strlen (data) + 1);
+ if (! newscore.user_data
+ || sprintf (newscore.user_data, "%s %s", user, data) < 0)
+ lose_syserr ("Memory exhausted");
if (lock_file (scorefile, &lockstate) < 0)
lose_syserr ("Failed to lock scores file");
- if (read_scores (scorefile, &scores, &scorecount) < 0)
+ if (read_scores (scorefile, &scores, &scorecount, &scorealloc) < 0)
{
unlock_file (scorefile, lockstate);
lose_syserr ("Failed to read scores file");
}
- push_score (&scores, &scorecount, newscore, user_id, newdata);
+ if (push_score (&scores, &scorecount, &scorealloc, &newscore) < 0)
+ {
+ unlock_file (scorefile, lockstate);
+ lose_syserr ("Failed to add score");
+ }
sort_scores (scores, scorecount, reverse);
/* Limit the number of scores. If we're using reverse sorting, then
also increment the beginning of the array, to skip over the
*smallest* scores. Otherwise, just decrementing the number of
scores suffices, since the smallest is at the end. */
- if (scorecount > MAX_SCORES)
+ if (scorecount > max_scores)
{
if (reverse)
- scores += (scorecount - MAX_SCORES);
- scorecount = MAX_SCORES;
+ scores += scorecount - max_scores;
+ scorecount = max_scores;
}
if (write_scores (scorefile, scores, scorecount) < 0)
{
unlock_file (scorefile, lockstate);
lose_syserr ("Failed to write scores file");
}
- unlock_file (scorefile, lockstate);
+ if (unlock_file (scorefile, lockstate) < 0)
+ lose_syserr ("Failed to unlock scores file");
exit (EXIT_SUCCESS);
}
-static int
-read_score (FILE *f, struct score_entry *score)
+static char *
+read_score (char *p, struct score_entry *score)
{
- int c;
- if (feof (f))
- return 1;
- while ((c = getc (f)) != EOF
- && isdigit (c))
- {
- score->score *= 10;
- score->score += (c-48);
- }
- while ((c = getc (f)) != EOF
- && isspace (c))
- ;
- if (c == EOF)
- return -1;
- ungetc (c, f);
-#ifdef HAVE_GETDELIM
- {
- size_t count = 0;
- if (getdelim (&score->username, &count, ' ', f) < 1
- || score->username == NULL)
- return -1;
- /* Trim the space */
- score->username[strlen (score->username)-1] = '\0';
- }
-#else
- {
- int unameread = 0;
- int unamelen = 30;
- char *username = malloc (unamelen);
- if (!username)
- return -1;
-
- while ((c = getc (f)) != EOF
- && !isspace (c))
- {
- if (unameread >= unamelen-1)
- if (!(username = realloc (username, unamelen *= 2)))
- return -1;
- username[unameread] = c;
- unameread++;
- }
- if (c == EOF)
- return -1;
- username[unameread] = '\0';
- score->username = username;
- }
-#endif
-#ifdef HAVE_GETLINE
- score->data = NULL;
- errno = 0;
- {
- size_t len;
- if (getline (&score->data, &len, f) < 0)
- return -1;
- score->data[strlen (score->data)-1] = '\0';
- }
-#else
- {
- int cur = 0;
- int len = 16;
- char *buf = malloc (len);
- if (!buf)
- return -1;
- while ((c = getc (f)) != EOF
- && c != '\n')
- {
- if (cur >= len-1)
- {
- if (!(buf = realloc (buf, len *= 2)))
- return -1;
- }
- buf[cur] = c;
- cur++;
- }
- score->data = buf;
- score->data[cur] = '\0';
- }
-#endif
- return 0;
+ score->score = p;
+ p = strchr (p, ' ');
+ if (!p)
+ return p;
+ *p++ = 0;
+ score->user_data = p;
+ p = strchr (p, '\n');
+ if (!p)
+ return p;
+ *p++ = 0;
+ return p;
}
static int
-read_scores (const char *filename, struct score_entry **scores, int *count)
+read_scores (const char *filename, struct score_entry **scores,
+ ptrdiff_t *count, ptrdiff_t *alloc)
{
- int readval, scorecount, cursize;
- struct score_entry *ret;
+ char *p, *filedata;
+ ptrdiff_t filesize, nread;
+ struct stat st;
FILE *f = fopen (filename, "r");
if (!f)
return -1;
- scorecount = 0;
- cursize = 16;
- ret = (struct score_entry *) malloc (sizeof (struct score_entry) * cursize);
- if (!ret)
+ if (fstat (fileno (f), &st) != 0)
return -1;
- while ((readval = read_score (f, &ret[scorecount])) == 0)
+ if (! (0 <= st.st_size && st.st_size < min (PTRDIFF_MAX, SIZE_MAX)))
{
- /* We encountered an error. */
- if (readval < 0)
- return -1;
- scorecount++;
- if (scorecount >= cursize)
+ errno = EOVERFLOW;
+ return -1;
+ }
+ filesize = st.st_size;
+ filedata = malloc (filesize + 1);
+ if (! filedata)
+ return -1;
+ nread = fread (filedata, 1, filesize + 1, f);
+ if (filesize < nread)
+ {
+ errno = 0;
+ return -1;
+ }
+ if (nread < filesize)
+ filesize = nread;
+ if (ferror (f) || fclose (f) != 0)
+ return -1;
+ filedata[filesize] = 0;
+ if (strlen (filedata) != filesize)
+ {
+ errno = 0;
+ return -1;
+ }
+
+ *scores = 0;
+ *count = *alloc = 0;
+ for (p = filedata; p < filedata + filesize; )
+ {
+ struct score_entry entry;
+ p = read_score (p, &entry);
+ if (!p)
{
- cursize *= 2;
- ret = (struct score_entry *)
- realloc (ret, (sizeof (struct score_entry) * cursize));
- if (!ret)
- return -1;
+ errno = 0;
+ return -1;
}
+ if (push_score (scores, count, alloc, &entry) < 0)
+ return -1;
}
- *count = scorecount;
- *scores = ret;
return 0;
}
{
const struct score_entry *sa = (const struct score_entry *) a;
const struct score_entry *sb = (const struct score_entry *) b;
- return (sb->score > sa->score) - (sb->score < sa->score);
+ char *sca = sa->score;
+ char *scb = sb->score;
+ size_t lena, lenb;
+ bool nega = *sca == '-';
+ bool negb = *scb == '-';
+ int diff = nega - negb;
+ if (diff)
+ return diff;
+ if (nega)
+ {
+ char *tmp = sca;
+ sca = scb + 1;
+ scb = tmp + 1;
+ }
+ lena = strlen (sca);
+ lenb = strlen (scb);
+ if (lena != lenb)
+ return lenb < lena ? -1 : 1;
+ return strcmp (scb, sca);
}
static int
score_compare_reverse (const void *a, const void *b)
{
- const struct score_entry *sa = (const struct score_entry *) a;
- const struct score_entry *sb = (const struct score_entry *) b;
- return (sa->score > sb->score) - (sa->score < sb->score);
+ return score_compare (b, a);
}
int
-push_score (struct score_entry **scores, int *count, int newscore, char *username, char *newdata)
+push_score (struct score_entry **scores, ptrdiff_t *count, ptrdiff_t *size,
+ struct score_entry const *newscore)
{
- struct score_entry *newscores
- = (struct score_entry *) realloc (*scores,
- sizeof (struct score_entry) * ((*count) + 1));
- if (!newscores)
- return -1;
- newscores[*count].score = newscore;
- newscores[*count].username = username;
- newscores[*count].data = newdata;
+ struct score_entry *newscores = *scores;
+ if (*count == *size)
+ {
+ ptrdiff_t newsize = *size;
+ if (newsize <= 0)
+ newsize = 1;
+ else if (newsize <= MAX_SCORES / 2)
+ newsize *= 2;
+ else if (newsize < MAX_SCORES)
+ newsize = MAX_SCORES;
+ else
+ {
+ errno = ENOMEM;
+ return -1;
+ }
+ newscores = realloc (newscores, sizeof *newscores * newsize);
+ if (!newscores)
+ return -1;
+ *scores = newscores;
+ *size = newsize;
+ }
+ newscores[*count] = *newscore;
(*count) += 1;
- *scores = newscores;
return 0;
}
static void
-sort_scores (struct score_entry *scores, int count, int reverse)
+sort_scores (struct score_entry *scores, ptrdiff_t count, bool reverse)
{
- qsort (scores, count, sizeof (struct score_entry),
- reverse ? score_compare_reverse : score_compare);
+ qsort (scores, count, sizeof *scores,
+ reverse ? score_compare_reverse : score_compare);
}
static int
-write_scores (const char *filename, const struct score_entry *scores, int count)
+write_scores (const char *filename, const struct score_entry *scores,
+ ptrdiff_t count)
{
+ int fd;
FILE *f;
- int i;
+ ptrdiff_t i;
char *tempfile = malloc (strlen (filename) + strlen (".tempXXXXXX") + 1);
if (!tempfile)
return -1;
strcpy (tempfile, filename);
strcat (tempfile, ".tempXXXXXX");
-#ifdef HAVE_MKSTEMP
- if (mkstemp (tempfile) < 0
-#else
- if (mktemp (tempfile) != tempfile
+ fd = mkostemp (tempfile, 0);
+ if (fd < 0)
+ return -1;
+#ifndef DOS_NT
+ if (fchmod (fd, 0644) != 0)
+ return -1;
#endif
- || !(f = fopen (tempfile, "w")))
+ f = fdopen (fd, "w");
+ if (! f)
return -1;
for (i = 0; i < count; i++)
- if (fprintf (f, "%ld %s %s\n", scores[i].score, scores[i].username,
- scores[i].data) < 0)
+ if (fprintf (f, "%s %s\n", scores[i].score, scores[i].user_data) < 0)
return -1;
- fclose (f);
- if (rename (tempfile, filename) < 0)
+ if (fclose (f) != 0)
return -1;
- if (chmod (filename, 0644) < 0)
+ if (rename (tempfile, filename) != 0)
return -1;
return 0;
}
strcpy (lockpath, filename);
strcat (lockpath, lockext);
*state = lockpath;
- trylock:
- attempts++;
- /* If the lock is over an hour old, delete it. */
- if (stat (lockpath, &buf) == 0
- && (difftime (buf.st_ctime, time (NULL) > 60*60)))
- unlink (lockpath);
- fd = open (lockpath, O_CREAT | O_EXCL, 0600);
- if (fd < 0)
+
+ while ((fd = open (lockpath, O_CREAT | O_EXCL, 0600)) < 0)
{
- if (errno == EEXIST)
+ if (errno != EEXIST)
+ return -1;
+ attempts++;
+
+ /* Break the lock if it is over an hour old, or if we've tried
+ more than MAX_ATTEMPTS times. We won't corrupt the file, but
+ we might lose some scores. */
+ if (MAX_ATTEMPTS < attempts
+ || (stat (lockpath, &buf) == 0 && 60 * 60 < time (0) - buf.st_ctime))
{
- /* Break the lock; we won't corrupt the file, but we might
- lose some scores. */
- if (attempts > MAX_ATTEMPTS)
- {
- unlink (lockpath);
- attempts = 0;
- }
- sleep ((rand () % 2)+1);
- goto trylock;
+ if (unlink (lockpath) != 0 && errno != ENOENT)
+ return -1;
+ attempts = 0;
}
- else
- return -1;
+
+ sleep ((rand () & 1) + 1);
}
+
close (fd);
return 0;
}
unlock_file (const char *filename, void *state)
{
char *lockpath = (char *) state;
- int ret = unlink (lockpath);
int saved_errno = errno;
+ int ret = unlink (lockpath);
+ int unlink_errno = errno;
free (lockpath);
- errno = saved_errno;
+ errno = ret < 0 ? unlink_errno : saved_errno;
return ret;
}
-
/* update-game-score.c ends here */