diff options
Diffstat (limited to 'tempfile.c')
| -rw-r--r-- | tempfile.c | 245 |
1 files changed, 128 insertions, 117 deletions
diff --git a/tempfile.c b/tempfile.c index 2990c92424..5fdafdd2d2 100644 --- a/tempfile.c +++ b/tempfile.c @@ -30,21 +30,19 @@ * `fdopen_tempfile()` has been called on the object * - `owner` holds the PID of the process that created the file * - * - Active, file closed (after successful `close_tempfile()`). Same + * - Active, file closed (after `close_tempfile_gently()`). Same * as the previous state, except that the temporary file is closed, * `fd` is -1, and `fp` is `NULL`. * - * - Inactive (after `delete_tempfile()`, `rename_tempfile()`, a - * failed attempt to create a temporary file, or a failed - * `close_tempfile()`). In this state: + * - Inactive (after `delete_tempfile()`, `rename_tempfile()`, or a + * failed attempt to create a temporary file). In this state: * * - `active` is unset * - `filename` is empty (usually, though there are transitory * states in which this condition doesn't hold). Client code should * *not* rely on the filename being empty in this state. * - `fd` is -1 and `fp` is `NULL` - * - the object is left registered in the `tempfile_list`, and - * `on_list` is set. + * - the object is removed from `tempfile_list` (but could be used again) * * A temporary file is owned by the process that created it. The * `tempfile` has an `owner` field that records the owner's PID. This @@ -56,20 +54,28 @@ #include "tempfile.h" #include "sigchain.h" -static struct tempfile *volatile tempfile_list; +static VOLATILE_LIST_HEAD(tempfile_list); -static void remove_tempfiles(int skip_fclose) +static void remove_tempfiles(int in_signal_handler) { pid_t me = getpid(); + volatile struct volatile_list_head *pos; - while (tempfile_list) { - if (tempfile_list->owner == me) { - /* fclose() is not safe to call in a signal handler */ - if (skip_fclose) - tempfile_list->fp = NULL; - delete_tempfile(tempfile_list); - } - tempfile_list = tempfile_list->next; + list_for_each(pos, &tempfile_list) { + struct tempfile *p = list_entry(pos, struct tempfile, list); + + if (!is_tempfile_active(p) || p->owner != me) + continue; + + if (p->fd >= 0) + close(p->fd); + + if (in_signal_handler) + unlink(p->filename.buf); + else + unlink_or_warn(p->filename.buf); + + p->active = 0; } } @@ -85,39 +91,48 @@ static void remove_tempfiles_on_signal(int signo) raise(signo); } -/* - * Initialize *tempfile if necessary and add it to tempfile_list. - */ -static void prepare_tempfile_object(struct tempfile *tempfile) +static struct tempfile *new_tempfile(void) { - if (!tempfile_list) { - /* One-time initialization */ + struct tempfile *tempfile = xmalloc(sizeof(*tempfile)); + tempfile->fd = -1; + tempfile->fp = NULL; + tempfile->active = 0; + tempfile->owner = 0; + INIT_LIST_HEAD(&tempfile->list); + strbuf_init(&tempfile->filename, 0); + return tempfile; +} + +static void activate_tempfile(struct tempfile *tempfile) +{ + static int initialized; + + if (is_tempfile_active(tempfile)) + BUG("activate_tempfile called for active object"); + + if (!initialized) { sigchain_push_common(remove_tempfiles_on_signal); atexit(remove_tempfiles_on_exit); + initialized = 1; } - if (tempfile->active) - die("BUG: prepare_tempfile_object called for active object"); - if (!tempfile->on_list) { - /* Initialize *tempfile and add it to tempfile_list: */ - tempfile->fd = -1; - tempfile->fp = NULL; - tempfile->active = 0; - tempfile->owner = 0; - strbuf_init(&tempfile->filename, 0); - tempfile->next = tempfile_list; - tempfile_list = tempfile; - tempfile->on_list = 1; - } else if (tempfile->filename.len) { - /* This shouldn't happen, but better safe than sorry. */ - die("BUG: prepare_tempfile_object called for improperly-reset object"); - } + volatile_list_add(&tempfile->list, &tempfile_list); + tempfile->owner = getpid(); + tempfile->active = 1; +} + +static void deactivate_tempfile(struct tempfile *tempfile) +{ + tempfile->active = 0; + strbuf_release(&tempfile->filename); + volatile_list_del(&tempfile->list); + free(tempfile); } /* Make sure errno contains a meaningful value on error */ -int create_tempfile(struct tempfile *tempfile, const char *path) +struct tempfile *create_tempfile(const char *path) { - prepare_tempfile_object(tempfile); + struct tempfile *tempfile = new_tempfile(); strbuf_add_absolute_path(&tempfile->filename, path); tempfile->fd = open(tempfile->filename.buf, @@ -127,52 +142,48 @@ int create_tempfile(struct tempfile *tempfile, const char *path) tempfile->fd = open(tempfile->filename.buf, O_RDWR | O_CREAT | O_EXCL, 0666); if (tempfile->fd < 0) { - strbuf_reset(&tempfile->filename); - return -1; + deactivate_tempfile(tempfile); + return NULL; } - tempfile->owner = getpid(); - tempfile->active = 1; + activate_tempfile(tempfile); if (adjust_shared_perm(tempfile->filename.buf)) { int save_errno = errno; error("cannot fix permission bits on %s", tempfile->filename.buf); - delete_tempfile(tempfile); + delete_tempfile(&tempfile); errno = save_errno; - return -1; + return NULL; } - return tempfile->fd; + + return tempfile; } -void register_tempfile(struct tempfile *tempfile, const char *path) +struct tempfile *register_tempfile(const char *path) { - prepare_tempfile_object(tempfile); + struct tempfile *tempfile = new_tempfile(); strbuf_add_absolute_path(&tempfile->filename, path); - tempfile->owner = getpid(); - tempfile->active = 1; + activate_tempfile(tempfile); + return tempfile; } -int mks_tempfile_sm(struct tempfile *tempfile, - const char *template, int suffixlen, int mode) +struct tempfile *mks_tempfile_sm(const char *template, int suffixlen, int mode) { - prepare_tempfile_object(tempfile); + struct tempfile *tempfile = new_tempfile(); strbuf_add_absolute_path(&tempfile->filename, template); tempfile->fd = git_mkstemps_mode(tempfile->filename.buf, suffixlen, mode); if (tempfile->fd < 0) { - strbuf_reset(&tempfile->filename); - return -1; + deactivate_tempfile(tempfile); + return NULL; } - tempfile->owner = getpid(); - tempfile->active = 1; - return tempfile->fd; + activate_tempfile(tempfile); + return tempfile; } -int mks_tempfile_tsm(struct tempfile *tempfile, - const char *template, int suffixlen, int mode) +struct tempfile *mks_tempfile_tsm(const char *template, int suffixlen, int mode) { + struct tempfile *tempfile = new_tempfile(); const char *tmpdir; - prepare_tempfile_object(tempfile); - tmpdir = getenv("TMPDIR"); if (!tmpdir) tmpdir = "/tmp"; @@ -180,35 +191,34 @@ int mks_tempfile_tsm(struct tempfile *tempfile, strbuf_addf(&tempfile->filename, "%s/%s", tmpdir, template); tempfile->fd = git_mkstemps_mode(tempfile->filename.buf, suffixlen, mode); if (tempfile->fd < 0) { - strbuf_reset(&tempfile->filename); - return -1; + deactivate_tempfile(tempfile); + return NULL; } - tempfile->owner = getpid(); - tempfile->active = 1; - return tempfile->fd; + activate_tempfile(tempfile); + return tempfile; } -int xmks_tempfile_m(struct tempfile *tempfile, const char *template, int mode) +struct tempfile *xmks_tempfile_m(const char *template, int mode) { - int fd; + struct tempfile *tempfile; struct strbuf full_template = STRBUF_INIT; strbuf_add_absolute_path(&full_template, template); - fd = mks_tempfile_m(tempfile, full_template.buf, mode); - if (fd < 0) + tempfile = mks_tempfile_m(full_template.buf, mode); + if (!tempfile) die_errno("Unable to create temporary file '%s'", full_template.buf); strbuf_release(&full_template); - return fd; + return tempfile; } FILE *fdopen_tempfile(struct tempfile *tempfile, const char *mode) { - if (!tempfile->active) - die("BUG: fdopen_tempfile() called for inactive object"); + if (!is_tempfile_active(tempfile)) + BUG("fdopen_tempfile() called for inactive object"); if (tempfile->fp) - die("BUG: fdopen_tempfile() called for open object"); + BUG("fdopen_tempfile() called for open object"); tempfile->fp = fdopen(tempfile->fd, mode); return tempfile->fp; @@ -216,95 +226,96 @@ FILE *fdopen_tempfile(struct tempfile *tempfile, const char *mode) const char *get_tempfile_path(struct tempfile *tempfile) { - if (!tempfile->active) - die("BUG: get_tempfile_path() called for inactive object"); + if (!is_tempfile_active(tempfile)) + BUG("get_tempfile_path() called for inactive object"); return tempfile->filename.buf; } int get_tempfile_fd(struct tempfile *tempfile) { - if (!tempfile->active) - die("BUG: get_tempfile_fd() called for inactive object"); + if (!is_tempfile_active(tempfile)) + BUG("get_tempfile_fd() called for inactive object"); return tempfile->fd; } FILE *get_tempfile_fp(struct tempfile *tempfile) { - if (!tempfile->active) - die("BUG: get_tempfile_fp() called for inactive object"); + if (!is_tempfile_active(tempfile)) + BUG("get_tempfile_fp() called for inactive object"); return tempfile->fp; } -int close_tempfile(struct tempfile *tempfile) +int close_tempfile_gently(struct tempfile *tempfile) { - int fd = tempfile->fd; - FILE *fp = tempfile->fp; + int fd; + FILE *fp; int err; - if (fd < 0) + if (!is_tempfile_active(tempfile) || tempfile->fd < 0) return 0; + fd = tempfile->fd; + fp = tempfile->fp; tempfile->fd = -1; if (fp) { tempfile->fp = NULL; - - /* - * Note: no short-circuiting here; we want to fclose() - * in any case! - */ - err = ferror(fp) | fclose(fp); + if (ferror(fp)) { + err = -1; + if (!fclose(fp)) + errno = EIO; + } else { + err = fclose(fp); + } } else { err = close(fd); } - if (err) { - int save_errno = errno; - delete_tempfile(tempfile); - errno = save_errno; - return -1; - } - - return 0; + return err ? -1 : 0; } int reopen_tempfile(struct tempfile *tempfile) { + if (!is_tempfile_active(tempfile)) + BUG("reopen_tempfile called for an inactive object"); if (0 <= tempfile->fd) - die("BUG: reopen_tempfile called for an open object"); - if (!tempfile->active) - die("BUG: reopen_tempfile called for an inactive object"); + BUG("reopen_tempfile called for an open object"); tempfile->fd = open(tempfile->filename.buf, O_WRONLY); return tempfile->fd; } -int rename_tempfile(struct tempfile *tempfile, const char *path) +int rename_tempfile(struct tempfile **tempfile_p, const char *path) { - if (!tempfile->active) - die("BUG: rename_tempfile called for inactive object"); + struct tempfile *tempfile = *tempfile_p; + + if (!is_tempfile_active(tempfile)) + BUG("rename_tempfile called for inactive object"); - if (close_tempfile(tempfile)) + if (close_tempfile_gently(tempfile)) { + delete_tempfile(tempfile_p); return -1; + } if (rename(tempfile->filename.buf, path)) { int save_errno = errno; - delete_tempfile(tempfile); + delete_tempfile(tempfile_p); errno = save_errno; return -1; } - tempfile->active = 0; - strbuf_reset(&tempfile->filename); + deactivate_tempfile(tempfile); + *tempfile_p = NULL; return 0; } -void delete_tempfile(struct tempfile *tempfile) +void delete_tempfile(struct tempfile **tempfile_p) { - if (!tempfile->active) + struct tempfile *tempfile = *tempfile_p; + + if (!is_tempfile_active(tempfile)) return; - if (!close_tempfile(tempfile)) { - unlink_or_warn(tempfile->filename.buf); - tempfile->active = 0; - strbuf_reset(&tempfile->filename); - } + close_tempfile_gently(tempfile); + unlink_or_warn(tempfile->filename.buf); + deactivate_tempfile(tempfile); + *tempfile_p = NULL; } |