X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/f5bceaf89b3b88f42da85cbce98cadf9429c3974..65396510c3ff5e5386560d586cb117f6a9d06c27:/lib-src/update-game-score.c diff --git a/lib-src/update-game-score.c b/lib-src/update-game-score.c index 084b54fdb3..8f7c90cad5 100644 --- a/lib-src/update-game-score.c +++ b/lib-src/update-game-score.c @@ -1,5 +1,5 @@ /* update-game-score.c --- Update a score file - Copyright (C) 2002 Free Software Foundation, Inc. + Copyright (C) 2002, 2003 Free Software Foundation, Inc. This file is part of GNU Emacs. @@ -19,44 +19,75 @@ the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* This program is allows a game to securely and atomically update a - score file. It should be installed setgid, owned by an appropriate - group like `games'. + score file. It should be installed setuid, owned by an appropriate + user like `games'. + + Alternatively, it can be compiled without HAVE_SHARED_GAME_DIR + defined, and in that case it will store scores in the user's home + directory (it should NOT be setuid). Created 2002/03/22, by Colin Walters */ -#define _GNU_SOURCE +#include +#ifdef HAVE_UNISTD_H #include +#endif #include +#ifdef HAVE_STRING_H #include +#endif +#ifdef HAVE_STDLIB_H #include +#endif #include #include #include #include +#ifdef HAVE_FCNTL_H #include +#endif +#ifdef STDC_HEADERS +#include +#endif #include -#include + +/* Needed for SunOS4, for instance. */ +extern char *optarg; +extern int optind, opterr; #define MAX_ATTEMPTS 5 -#define SCORE_FILE_PREFIX "/var/games/emacs/" +#define MAX_SCORES 200 +#define MAX_DATA_LEN 1024 + +/* Declare the prototype for a general external function. */ +#if defined (PROTOTYPES) || defined (WINDOWSNT) +#define P_(proto) proto +#else +#define P_(proto) () +#endif + +#ifndef HAVE_DIFFTIME +/* OK on POSIX (time_t is arithmetic type) modulo overflow in subtraction. */ +#define difftime(t1, t0) (double)((t1) - (t0)) +#endif int -usage(int err) +usage (err) + int err; { - fprintf(stdout, "Usage: update-game-score [-m MAX ] [ -r ] game/scorefile SCORE DATA\n"); - fprintf(stdout, " update-game-score -h\n"); - fprintf(stdout, " -h\t\tDisplay this help.\n"); - fprintf(stdout, " -m MAX\t\tLimit the maximum number of scores to MAX.\n"); - fprintf(stdout, " -r\t\tSort the scores in increasing order.\n"); - exit(err); + fprintf (stdout, "Usage: update-game-score [-m MAX ] [ -r ] game/scorefile SCORE DATA\n"); + fprintf (stdout, " update-game-score -h\n"); + fprintf (stdout, " -h\t\tDisplay this help.\n"); + fprintf (stdout, " -m MAX\t\tLimit the maximum number of scores to MAX.\n"); + fprintf (stdout, " -r\t\tSort the scores in increasing order.\n"); + fprintf (stdout, " -d DIR\t\tStore scores in DIR (only if not setuid).\n"); + exit (err); } -int -lock_file(const char *filename, void **state); -int -unlock_file(const char *filename, void *state); +int lock_file P_ ((const char *filename, void **state)); +int unlock_file P_ ((const char *filename, void *state)); struct score_entry { @@ -65,158 +96,226 @@ struct score_entry char *data; }; -int -read_scores(const char *filename, struct score_entry **scores, - int *count); -int -push_score(struct score_entry **scores, int *count, - int newscore, char *username, char *newdata); +int read_scores P_ ((const char *filename, struct score_entry **scores, + int *count)); +int push_score P_ ((struct score_entry **scores, int *count, + int newscore, char *username, char *newdata)); +void sort_scores P_ ((struct score_entry *scores, int count, int reverse)); +int write_scores P_ ((const char *filename, const struct score_entry *scores, + int count)); + +void lose P_ ((const char *msg)) NO_RETURN; + void -sort_scores(struct score_entry *scores, int count, int reverse); -int -write_scores(const char *filename, const struct score_entry *scores, - int count); +lose (msg) + const char *msg; +{ + fprintf (stderr, "%s\n", msg); + exit (EXIT_FAILURE); +} +void lose_syserr P_ ((const char *msg)) NO_RETURN; + +/* Taken from sysdep.c. */ +#ifndef HAVE_STRERROR +#ifndef WINDOWSNT char * -get_user_id() +strerror (errnum) + int errnum; +{ + extern char *sys_errlist[]; + extern int sys_nerr; + + if (errnum >= 0 && errnum < sys_nerr) + return sys_errlist[errnum]; + return (char *) "Unknown error"; +} +#endif /* not WINDOWSNT */ +#endif /* ! HAVE_STRERROR */ + +void +lose_syserr (msg) + const char *msg; +{ + fprintf (stderr, "%s: %s\n", msg, strerror (errno)); + exit (EXIT_FAILURE); +} + +char * +get_user_id P_ ((void)) { char *name; - struct passwd *buf = getpwuid(getuid()); + struct passwd *buf = getpwuid (getuid ()); if (!buf) { int count = 1; - int uid = (int) getuid(); - while (uid /= 10) + int uid = (int) getuid (); + int tuid = uid; + while (tuid /= 10) count++; - name = malloc(count+1); - sprintf(name, "%d", uid); + name = malloc (count+1); + if (!name) + return NULL; + sprintf (name, "%d", uid); return name; } return buf->pw_name; } +char * +get_prefix (running_suid, user_prefix) + int running_suid; + char *user_prefix; +{ + if (!running_suid && user_prefix == NULL) + lose ("Not using a shared game directory, and no prefix given."); + if (running_suid) + { +#ifdef HAVE_SHARED_GAME_DIR + return HAVE_SHARED_GAME_DIR; +#else + lose ("This program was compiled without HAVE_SHARED_GAME_DIR,\n and should not be suid."); +#endif + } + return user_prefix; +} + int -main(int argc, char **argv) +main (argc, argv) + int argc; + char **argv; { - int c; + int c, running_suid; void *lockstate; - char *scorefile; + char *user_id, *scorefile, *prefix, *user_prefix = NULL; struct stat buf; struct score_entry *scores; - int newscore, scorecount, reverse = 0, max = -1; + int newscore, scorecount, reverse = 0, max = MAX_SCORES; char *newdata; - srand(time(0)); + srand (time (0)); - while ((c = getopt(argc, argv, "hrm:")) != -1) + while ((c = getopt (argc, argv, "hrm:d:")) != -1) switch (c) { case 'h': - usage(0); + usage (EXIT_SUCCESS); + break; + case 'd': + user_prefix = optarg; break; case 'r': reverse = 1; break; case 'm': - max = atoi(optarg); + max = atoi (optarg); + if (max > MAX_SCORES) + max = MAX_SCORES; break; default: - usage(1); + usage (EXIT_FAILURE); } if (optind+3 != argc) - usage(1); - scorefile = malloc(strlen(SCORE_FILE_PREFIX) + strlen(argv[optind]) + 1); + usage (EXIT_FAILURE); + + running_suid = (getuid () != geteuid ()); + + prefix = get_prefix (running_suid, user_prefix); + + scorefile = malloc (strlen (prefix) + strlen (argv[optind]) + 2); if (!scorefile) - { - fprintf(stderr, "Couldn't create score file name: %s\n", - strerror(errno)); - goto fail; - } - strcpy(scorefile, SCORE_FILE_PREFIX); - strcat(scorefile, argv[optind]); - newscore = atoi(argv[optind+1]); + lose_syserr ("Couldn't allocate score file"); + + strcpy (scorefile, prefix); + strcat (scorefile, "/"); + strcat (scorefile, argv[optind]); + newscore = atoi (argv[optind+1]); newdata = argv[optind+2]; - - if (stat(scorefile, &buf) < 0) - { - fprintf(stderr, "Failed to access scores file \"%s\": %s\n", - scorefile, strerror(errno)); - goto fail; - } - if (lock_file(scorefile, &lockstate) < 0) - { - fprintf(stderr, "Failed to lock scores file \"%s\": %s\n", - scorefile, strerror(errno)); - goto fail; - } - if (read_scores(scorefile, &scores, &scorecount) < 0) + 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"); + + if (stat (scorefile, &buf) < 0) + lose_syserr ("Failed to access scores file"); + + if (lock_file (scorefile, &lockstate) < 0) + lose_syserr ("Failed to lock scores file"); + + if (read_scores (scorefile, &scores, &scorecount) < 0) { - fprintf(stderr, "Failed to read scores file \"%s\": %s\n", - scorefile, strerror(errno)); - goto fail_unlock; + unlock_file (scorefile, lockstate); + lose_syserr ("Failed to read scores file"); } - push_score(&scores, &scorecount, newscore, get_user_id(), newdata); - sort_scores(scores, scorecount, reverse); - if (write_scores(scorefile, scores, scorecount) < 0) + push_score (&scores, &scorecount, newscore, user_id, newdata); + /* Limit the number of scores. If we're using reverse sorting, then + we should increment the beginning of the array, to skip over the + *smallest* scores. Otherwise, we just decrement the number of + scores, since the smallest will be at the end. */ + if (scorecount > MAX_SCORES) + scorecount -= (scorecount - MAX_SCORES); + if (reverse) + scores += (scorecount - MAX_SCORES); + sort_scores (scores, scorecount, reverse); + if (write_scores (scorefile, scores, scorecount) < 0) { - fprintf(stderr, "Failed to write scores file \"%s\": %s\n", - scorefile, strerror(errno)); - goto fail_unlock; + unlock_file (scorefile, lockstate); + lose_syserr ("Failed to write scores file"); } - unlock_file(scorefile, lockstate); - exit(0); - fail_unlock: - unlock_file(scorefile, lockstate); - fail: - exit(1); + unlock_file (scorefile, lockstate); + exit (EXIT_SUCCESS); } int -read_score(FILE *f, struct score_entry *score) +read_score (f, score) + FILE *f; + struct score_entry *score; { int c; - if (feof(f)) + if (feof (f)) return 1; - while ((c = getc(f)) != EOF - && isdigit(c)) + while ((c = getc (f)) != EOF + && isdigit (c)) { score->score *= 10; score->score += (c-48); } - while ((c = getc(f)) != EOF - && isspace(c)) + while ((c = getc (f)) != EOF + && isspace (c)) ; if (c == EOF) return -1; - ungetc(c, f); + ungetc (c, f); #ifdef HAVE_GETDELIM { - int count = 0; - if (getdelim(&score->username, &count, ' ', f) < 1 + 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); + char *username = malloc (unamelen); if (!username) return -1; - - while ((c = getc(f)) != EOF - && !isspace(c)) + + while ((c = getc (f)) != EOF + && !isspace (c)) { - if (unameread == unamelen) - { - if (!(username = realloc(username, unamelen *= 2))) - return -1; - } + if (unameread >= unamelen-1) + if (!(username = realloc (username, unamelen *= 2))) + return -1; username[unameread] = c; unameread++; } - if (c == EOF) + if (c == EOF) return -1; username[unameread] = '\0'; score->username = username; @@ -224,53 +323,55 @@ read_score(FILE *f, struct score_entry *score) #endif #ifdef HAVE_GETLINE score->data = NULL; - errno = ESUCCES; + errno = 0; { - int len; - if (getline(&score->data, &len, f) < 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); + char *buf = malloc (len); if (!buf) return -1; - while ((c = getc(f)) != EOF + while ((c = getc (f)) != EOF && c != '\n') { if (cur >= len-1) { - if (!(buf = realloc(buf, len *= 2))) + if (!(buf = realloc (buf, len *= 2))) return -1; } buf[cur] = c; cur++; } score->data = buf; + score->data[cur] = '\0'; } #endif - /* Trim the newline */ - score->data[strlen(score->data)-1] = '\0'; return 0; } int -read_scores(const char *filename, struct score_entry **scores, - int *count) +read_scores (filename, scores, count) + const char *filename; + struct score_entry **scores; + int *count; { int readval, scorecount, cursize; struct score_entry *ret; - FILE *f = fopen(filename, "r"); - if (!f) + FILE *f = fopen (filename, "r"); + if (!f) return -1; scorecount = 0; cursize = 16; - ret = malloc(sizeof(struct score_entry) * cursize); - if (!ret) + ret = (struct score_entry *) malloc (sizeof (struct score_entry) * cursize); + if (!ret) return -1; - while ((readval = read_score(f, &ret[scorecount])) == 0) + while ((readval = read_score (f, &ret[scorecount])) == 0) { /* We encoutered an error */ if (readval < 0) @@ -278,7 +379,9 @@ read_scores(const char *filename, struct score_entry **scores, scorecount++; if (scorecount >= cursize) { - ret = realloc(ret, cursize *= 2); + cursize *= 2; + ret = (struct score_entry *) + realloc (ret, (sizeof (struct score_entry) * cursize)); if (!ret) return -1; } @@ -289,7 +392,9 @@ read_scores(const char *filename, struct score_entry **scores, } int -score_compare(const void *a, const void *b) +score_compare (a, b) + 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; @@ -297,7 +402,9 @@ score_compare(const void *a, const void *b) } int -score_compare_reverse(const void *a, const void *b) +score_compare_reverse (a, b) + 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; @@ -305,11 +412,15 @@ score_compare_reverse(const void *a, const void *b) } int -push_score(struct score_entry **scores, int *count, - int newscore, char *username, char *newdata) +push_score (scores, count, newscore, username, newdata) + struct score_entry **scores; + int *count; int newscore; + char *username; + char *newdata; { - struct score_entry *newscores = realloc(*scores, - sizeof(struct score_entry) * ((*count) + 1)); + struct score_entry *newscores + = (struct score_entry *) realloc (*scores, + sizeof (struct score_entry) * ((*count) + 1)); if (!newscores) return -1; newscores[*count].score = newscore; @@ -319,129 +430,106 @@ push_score(struct score_entry **scores, int *count, *scores = newscores; return 0; } - + void -sort_scores(struct score_entry *scores, int count, int reverse) +sort_scores (scores, count, reverse) + struct score_entry *scores; + int count; + int reverse; { - qsort(scores, count, sizeof(struct score_entry), + qsort (scores, count, sizeof (struct score_entry), reverse ? score_compare_reverse : score_compare); } int -write_scores(const char *filename, const struct score_entry *scores, - int count) +write_scores (filename, scores, count) + const char *filename; + const struct score_entry * scores; + int count; { - FILE *f; + FILE *f; int i; - char *tempfile = malloc(strlen(filename) + strlen(".tempXXXXXX") + 1); + char *tempfile = malloc (strlen (filename) + strlen (".tempXXXXXX") + 1); if (!tempfile) return -1; - strcpy(tempfile, filename); - strcat(tempfile, ".tempXXXXXX"); - if (mkstemp(tempfile) < 0 - || !(f = fopen(tempfile, "w"))) + strcpy (tempfile, filename); + strcat (tempfile, ".tempXXXXXX"); +#ifdef HAVE_MKSTEMP + if (mkstemp (tempfile) < 0 +#else + if (mktemp (tempfile) != tempfile +#endif + || !(f = fopen (tempfile, "w"))) return -1; for (i = 0; i < count; i++) - if (fprintf(f, "%ld %s %s\n", scores[i].score, scores[i].username, + if (fprintf (f, "%ld %s %s\n", scores[i].score, scores[i].username, scores[i].data) < 0) return -1; - fclose(f); - rename(tempfile, filename); - return 0; -} - -#if 0 -int -lock_file(const char *filename, void **state) -{ - struct flock lock; - int *istate; - int fd, attempts = 0, ret = 0; - lock.l_type = F_WRLCK; - lock.l_whence = SEEK_SET; - lock.l_start = 0; - lock.l_len = 0; - istate = malloc(sizeof(int)); - if (!istate) + fclose (f); + if (rename (tempfile, filename) < 0) return -1; - if ((fd = open(filename, O_RDWR, 0600)) < 0) + if (chmod (filename, 0644) < 0) return -1; - *istate = fd; - trylock: - attempts++; - if ((ret = fcntl(fd, F_GETLK, &lock)) == -1) - { - if (ret == EACCES || ret == EAGAIN) - if (attempts > MAX_ATTEMPTS) - exit(1); - else - { - sleep((rand() % 3)+1); - goto trylock; - } - else - ret = 0 ; - } - else - ret = 0; - *state = istate; - return ret; + return 0; } int -unlock_file(const char *filename, void *state) -{ - int fd, ret; - fd = *((int *) state); - free(state); - ret = close(fd); - return ret; -} - -#else - -int -lock_file(const char *filename, void **state) +lock_file (filename, state) + const char *filename; + void **state; { int fd; + struct stat buf; int attempts = 0; char *lockext = ".lockfile"; - char *lockpath = malloc(strlen(filename) + strlen(lockext) + 60); + char *lockpath = malloc (strlen (filename) + strlen (lockext) + 60); if (!lockpath) return -1; - strcpy(lockpath, filename); - strcat(lockpath, lockext); + strcpy (lockpath, filename); + strcat (lockpath, lockext); *state = lockpath; trylock: attempts++; - if ((fd = open(lockpath, O_CREAT | O_EXCL, 0600)) < 0) + /* 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) { if (errno == EEXIST) { /* Break the lock; we won't corrupt the file, but we might lose some scores. */ if (attempts > MAX_ATTEMPTS) - unlink(lockpath); - else - sleep((rand() % 2)+1); + { + unlink (lockpath); + attempts = 0; + } + sleep ((rand () % 2)+1); goto trylock; } else return -1; } - close(fd); + close (fd); return 0; } int -unlock_file(const char *filename, void *state) +unlock_file (filename, state) + const char *filename; + void *state; { char *lockpath = (char *) state; - int ret = unlink(lockpath); + int ret = unlink (lockpath); int saved_errno = errno; - free(lockpath); + free (lockpath); errno = saved_errno; return ret; } -#endif +/* arch-tag: 2bf5c52e-4beb-463a-954e-c58b9c64736b + (do not change this comment) */ + +/* update-game-score.c ends here */