Let afs callbacks return an error code.

It was a design mistake that callbacks have no way to tell whether
they were successful. This commit changes the callback_function
typedef so that callbacks return int instead of void.

Naturally, every callback must be adjusted accordingly. Doing so would
make the patch a bit large, so as a first step we make all callbacks
(except path_brother_callback() and hash_sister_callback() which
are special) return zero. The return value is ignored at the moment,
so the changes of this commit have no effect yet.

diff --git a/afs.c b/afs.c
index 0b2a4765b16f82fbde4674ac230bda4d2b5f9e18..24e737b67e3995c8723cd1d7ae7f72899554c322 100644 (file)
--- a/afs.c
+++ b/afs.c
@@ -578,7 +578,7 @@ void flush_and_free_pb(struct para_buffer *pb)
        free(pb->buf);
 }
 
-static void com_select_callback(int fd, const struct osl_object *query)
+static int com_select_callback(int fd, const struct osl_object *query)
 {
        struct para_buffer pb = {
                .max_size = shm_get_shmmax(),
@@ -617,6 +617,7 @@ static void com_select_callback(int fd, const struct osl_object *query)
                        num_admissible);
 out:
        flush_and_free_pb(&pb);
+       return 0;
 }
 
 int com_select(struct command_context *cc)
@@ -1005,7 +1006,7 @@ out:
        exit(EXIT_FAILURE);
 }
 
-static void create_tables_callback(int fd, const struct osl_object *query)
+static int create_tables_callback(int fd, const struct osl_object *query)
 {
        uint32_t table_mask = *(uint32_t *)query->data;
        int i, ret;
@@ -1035,6 +1036,7 @@ out:
        if (ret < 0)
                para_printf(&pb, "%s\n", para_strerror(-ret));
        flush_and_free_pb(&pb);
+       return 0;
 }
 
 int com_init(struct command_context *cc)

diff --git a/afs.h b/afs.h
index feada5b622c642ee7ae9fffd243551ffce2dc2f8..efd7fbacf61d1bea136e7162c14407c66b457b82 100644 (file)
--- a/afs.h
+++ b/afs.h
@@ -166,7 +166,7 @@ struct pattern_match_data {
  *
  * \sa send_callback_request().
  */
-typedef void callback_function(int fd, const struct osl_object *);
+typedef int callback_function(int fd, const struct osl_object *);
 
 /**
  * Callbacks send chunks to data back to the command handler. Pointers to
@@ -252,12 +252,12 @@ int get_afsi_of_row(const struct osl_row *row, struct afs_info *afsi);
 int get_afhi_of_row(const struct osl_row *row, struct afh_info *afhi);
 int get_audio_file_path_of_row(const struct osl_row *row, char **path);
 int audio_file_loop(void *private_data, osl_rbtree_loop_func *func);
-void aft_check_callback(int fd, __a_unused const struct osl_object *query);
+int aft_check_callback(int fd, __a_unused const struct osl_object *query);
 
 /* playlist */
 int playlist_open(char *name);
 void playlist_close(void);
-void playlist_check_callback(int fd, __a_unused const struct osl_object *query);
+int playlist_check_callback(int fd, __a_unused const struct osl_object *query);
 
 /** evaluates to 1 if x < y, to -1 if x > y and to 0 if x == y */
 #define NUM_COMPARE(x, y) ((int)((x) < (y)) - (int)((x) > (y)))

diff --git a/aft.c b/aft.c
index 16de67634677c4ba75774bc9453ae427f4581a13..acb6c6bf879f838976652ca3c48cfbf3ff75f70c 100644 (file)
--- a/aft.c
+++ b/aft.c
@@ -1291,7 +1291,7 @@ err:
        return ret;
 }
 
-static void com_ls_callback(int fd, const struct osl_object *query)
+static int com_ls_callback(int fd, const struct osl_object *query)
 {
        struct ls_options *opts = query->data;
        char *p, *pattern_start = (char *)query->data + sizeof(*opts);
@@ -1348,6 +1348,7 @@ out:
        free(opts->data);
        free(opts->data_ptr);
        free(opts->patterns);
+       return 0;
 }
 
 /*
@@ -1612,7 +1613,7 @@ enum com_add_flags {
        ADD_FLAG_ALL = 8,
 };
 
-static void com_add_callback(int fd, const struct osl_object *query)
+static int com_add_callback(int fd, const struct osl_object *query)
 {
        char *buf = query->data, *path;
        struct osl_row *pb, *aft_row;
@@ -1738,6 +1739,7 @@ out:
        if (ret < 0)
                para_printf(&msg, "%s\n", para_strerror(-ret));
        flush_and_free_pb(&msg);
+       return 0;
 }
 
 /** Used by com_add(). */
@@ -1748,26 +1750,26 @@ struct private_add_data {
        uint32_t flags;
 };
 
-static void path_brother_callback(int fd, const struct osl_object *query)
+static int path_brother_callback(int fd, const struct osl_object *query)
 {
        char *path = query->data;
        struct osl_row *path_brother;
        int ret = aft_get_row_of_path(path, &path_brother);
        if (ret < 0)
-               return;
-       pass_buffer_as_shm(fd, SBD_OUTPUT, (char *)&path_brother,
+               return ret;
+       return pass_buffer_as_shm(fd, SBD_OUTPUT, (char *)&path_brother,
                sizeof(path_brother));
 }
 
-static void hash_sister_callback(int fd, const struct osl_object *query)
+static int hash_sister_callback(int fd, const struct osl_object *query)
 {
        unsigned char *hash = query->data;
        struct osl_row *hash_sister;
 
        hash_sister = find_hash_sister(hash);
        if (!hash_sister)
-               return;
-       pass_buffer_as_shm(fd, SBD_OUTPUT, (char *)&hash_sister,
+               return 0;
+       return pass_buffer_as_shm(fd, SBD_OUTPUT, (char *)&hash_sister,
                sizeof(hash_sister));
 }
 
@@ -2009,7 +2011,7 @@ static int touch_audio_file(__a_unused struct osl_table *table,
        return 1;
 }
 
-static void com_touch_callback(int fd, const struct osl_object *query)
+static int com_touch_callback(int fd, const struct osl_object *query)
 {
        struct touch_action_data tad = {.cto = query->data,
                .pb = {
@@ -2039,6 +2041,7 @@ static void com_touch_callback(int fd, const struct osl_object *query)
        else if (pmd.num_matches == 0)
                para_printf(&tad.pb, "no matches\n");
        flush_and_free_pb(&tad.pb);
+       return 0;
 }
 
 int com_touch(struct command_context *cc)
@@ -2148,7 +2151,7 @@ static int remove_audio_file(__a_unused struct osl_table *table,
        return ret;
 }
 
-static void com_rm_callback(int fd, const struct osl_object *query)
+static int com_rm_callback(int fd, const struct osl_object *query)
 {
        struct com_rm_action_data crd = {.flags = *(uint32_t *)query->data,
                .pb = {
@@ -2175,13 +2178,14 @@ static void com_rm_callback(int fd, const struct osl_object *query)
        ret = for_each_matching_row(&pmd);
        if (ret < 0) {
                para_printf(&crd.pb, "%s\n", para_strerror(-ret));
-               return;
+               return 0;
        }
        if ((pmd.num_matches == 0) && !(crd.flags & RM_FLAG_FORCE))
                para_printf(&crd.pb, "no matches -- nothing removed\n");
        else if (crd.flags & RM_FLAG_VERBOSE)
                para_printf(&crd.pb, "removed %u files\n", pmd.num_matches);
        flush_and_free_pb(&crd.pb);
+       return 0;
 }
 
 /* TODO options: -r (recursive) */
@@ -2285,7 +2289,7 @@ static int copy_selector_info(__a_unused struct osl_table *table,
        return 1;
 }
 
-static void com_cpsi_callback(int fd, const struct osl_object *query)
+static int com_cpsi_callback(int fd, const struct osl_object *query)
 {
        struct cpsi_action_data cad = {
                .flags = *(unsigned *)query->data,
@@ -2325,6 +2329,7 @@ out:
        } else
                para_printf(&cad.pb, "no matches - nothing copied\n");
        flush_and_free_pb(&cad.pb);
+       return 0;
 }
 
 int com_cpsi(struct command_context *cc)
@@ -2409,7 +2414,7 @@ static int change_atts(__a_unused struct osl_table *table,
        return 1;
 }
 
-static void com_setatt_callback(int fd, const struct osl_object *query)
+static int com_setatt_callback(int fd, const struct osl_object *query)
 {
        char *p;
        int ret;
@@ -2470,6 +2475,7 @@ out:
        if (ret < 0)
                para_printf(&cad.pb, "%s\n", para_strerror(-ret));
        flush_and_free_pb(&cad.pb);
+       return 0;
 }
 
 int com_setatt(struct command_context *cc)
@@ -2480,15 +2486,15 @@ int com_setatt(struct command_context *cc)
                com_setatt_callback, afs_cb_result_handler, cc);
 }
 
-static void afs_stat_callback(int fd, const struct osl_object *query)
+static int afs_stat_callback(int fd, const struct osl_object *query)
 {
        int *parser_friendly = query->data;
        char *buf = *parser_friendly?
                parser_friendly_status_items : status_items;
 
        if (!buf)
-               return;
-       pass_buffer_as_shm(fd, SBD_OUTPUT, buf, strlen(buf));
+               return 0;
+       return pass_buffer_as_shm(fd, SBD_OUTPUT, buf, strlen(buf));
 }
 
 /**
@@ -2554,11 +2560,11 @@ static int check_audio_file(struct osl_row *row, void *data)
  * \param fd The afs socket.
  * \param query Unused.
  *
- * This function always succeeds.
+ * \return This function always returns zero.
  *
  * \sa com_check().
  */
-void aft_check_callback(int fd, __a_unused const struct osl_object *query)
+int aft_check_callback(int fd, __a_unused const struct osl_object *query)
 {
        struct para_buffer pb = {
                .max_size = shm_get_shmmax(),
@@ -2571,6 +2577,7 @@ void aft_check_callback(int fd, __a_unused const struct osl_object *query)
        para_printf(&pb, "checking audio file table...\n");
        audio_file_loop(&pb, check_audio_file);
        flush_and_free_pb(&pb);
+       return 0;
 }
 
 /**

diff --git a/attribute.c b/attribute.c
index 0c23addf3228fb753f5ded3b49dafb45f4d5823e..7da525eb90c7f6feef5a8af631e2be06e4b38dca 100644 (file)
--- a/attribute.c
+++ b/attribute.c
@@ -149,7 +149,7 @@ static int print_attribute(struct osl_table *table, struct osl_row *row,
        return 1;
 }
 
-static void com_lsatt_callback(int fd, const struct osl_object *query)
+static int com_lsatt_callback(int fd, const struct osl_object *query)
 {
        struct lsatt_action_data laad = {
                .flags = *(unsigned *) query->data,
@@ -179,6 +179,7 @@ static void com_lsatt_callback(int fd, const struct osl_object *query)
                pmd.pm_flags |= PM_REVERSE_LOOP;
        for_each_matching_row(&pmd);
        flush_and_free_pb(&laad.pb);
+       return 0;
 }
 
 int com_lsatt(struct command_context *cc)
@@ -223,7 +224,7 @@ struct addatt_event_data {
 };
 
 
-static void com_addatt_callback(int fd, const struct osl_object *query)
+static int com_addatt_callback(int fd, const struct osl_object *query)
 {
        char *p;
        int ret = 1;
@@ -285,6 +286,7 @@ out:
        if (ret < 0)
                para_printf(&pb, "%s: %s\n", p, para_strerror(-ret));
        flush_and_free_pb(&pb);
+       return 0;
 }
 
 int com_addatt(struct command_context *cc)
@@ -300,7 +302,7 @@ int com_addatt(struct command_context *cc)
        return ret;
 }
 
-static void com_mvatt_callback(int fd, const struct osl_object *query)
+static int com_mvatt_callback(int fd, const struct osl_object *query)
 {
        char *old = query->data;
        size_t size = strlen(old) + 1;
@@ -329,6 +331,7 @@ out:
        else
                afs_event(ATTRIBUTE_RENAME, &pb, NULL);
        flush_and_free_pb(&pb);
+       return 0;
 }
 
 int com_mvatt(struct command_context *cc)
@@ -379,7 +382,7 @@ static int remove_attribute(struct osl_table *table, struct osl_row *row,
        return 1;
 }
 
-static void com_rmatt_callback(int fd, const struct osl_object *query)
+static int com_rmatt_callback(int fd, const struct osl_object *query)
 {
        struct remove_attribute_action_data raad = {
                .num_removed = 0,
@@ -407,6 +410,7 @@ static void com_rmatt_callback(int fd, const struct osl_object *query)
        else if (!raad.num_removed)
                para_printf(&raad.pb, "no match -- nothing removed\n");
        flush_and_free_pb(&raad.pb);
+       return 0;
 }
 
 int com_rmatt(struct command_context *cc)

diff --git a/blob.c b/blob.c
index 47253b5e08811c7fbb4a2c2aa12e6f368307454c..5eb125c8262f6b34aaff506f9c6cb1310fa5916d 100644 (file)
--- a/blob.c
+++ b/blob.c
@@ -130,7 +130,7 @@ static int print_blob(struct osl_table *table, struct osl_row *row,
        return 1;
 }
 
-static void com_lsblob_callback(struct osl_table *table,
+static int com_lsblob_callback(struct osl_table *table,
                int fd, const struct osl_object *query)
 {
        struct lsblob_action_data lbad = {
@@ -167,6 +167,7 @@ static void com_lsblob_callback(struct osl_table *table,
        else if (pmd.num_matches == 0 && pmd.patterns.size > 0)
                para_printf(&lbad.pb, "no matches\n");
        flush_and_free_pb(&lbad.pb);
+       return 0;
 }
 
 static int com_lsblob(callback_function *f, struct command_context *cc)
@@ -218,7 +219,7 @@ static int cat_blob(struct osl_table *table, struct osl_row *row,
        return (ret < 0)? ret : ret2;
 }
 
-static void com_catblob_callback(struct osl_table *table, int fd,
+static int com_catblob_callback(struct osl_table *table, int fd,
                const struct osl_object *query)
 {
        struct pattern_match_data pmd = {
@@ -235,6 +236,7 @@ static void com_catblob_callback(struct osl_table *table, int fd,
                char err_msg[] = "no matches\n";
                pass_buffer_as_shm(fd, SBD_OUTPUT, err_msg, sizeof(err_msg));
        }
+       return 0;
 }
 
 static int com_catblob(callback_function *f, struct command_context *cc)
@@ -263,7 +265,7 @@ static int remove_blob(struct osl_table *table, struct osl_row *row,
        return 1;
 }
 
-static void com_rmblob_callback(struct osl_table *table, int fd,
+static int com_rmblob_callback(struct osl_table *table, int fd,
                const struct osl_object *query)
 {
        int ret;
@@ -296,6 +298,7 @@ static void com_rmblob_callback(struct osl_table *table, int fd,
                afs_event(BLOB_RENAME, NULL, table);
        }
        flush_and_free_pb(&rmbd.pb);
+       return 0;
 }
 
 static int com_rmblob(callback_function *f, struct command_context *cc)
@@ -306,7 +309,7 @@ static int com_rmblob(callback_function *f, struct command_context *cc)
                afs_cb_result_handler, cc);
 }
 
-static void com_addblob_callback(struct osl_table *table, int fd,
+static int com_addblob_callback(struct osl_table *table, int fd,
                const struct osl_object *query)
 {
        struct osl_object objs[NUM_BLOB_COLUMNS];
@@ -382,6 +385,7 @@ out:
                msg_len = xasprintf(&msg, "added %s as id %u\n", name, id);
        pass_buffer_as_shm(fd, SBD_OUTPUT, msg, msg_len);
        free(msg);
+       return 0;
 }
 
 /* Write input from fd to dynamically allocated buffer, but maximal 10M. */
@@ -466,7 +470,7 @@ static int com_addblob(callback_function *f, struct command_context *cc)
        return stdin_command(cc, &arg_obj, f);
 }
 
-static void com_mvblob_callback(struct osl_table *table, int fd,
+static int com_mvblob_callback(struct osl_table *table, int fd,
                const struct osl_object *query)
 {
        char *src = (char *) query->data;
@@ -496,6 +500,7 @@ static void com_mvblob_callback(struct osl_table *table, int fd,
        afs_event(BLOB_RENAME, NULL, table);
 out:
        flush_and_free_pb(&pb);
+       return 0;
 }
 
 static int com_mvblob(callback_function *f, struct command_context *cc)
@@ -512,7 +517,7 @@ static int com_mvblob(callback_function *f, struct command_context *cc)
 }
 
 #define DEFINE_BLOB_COMMAND(cmd_name, table_name, cmd_prefix) \
-       static void com_ ## cmd_name ## cmd_prefix ## _callback(int fd, const struct osl_object *query) \
+       static int com_ ## cmd_name ## cmd_prefix ## _callback(int fd, const struct osl_object *query) \
        { \
                return com_ ## cmd_name ## blob_callback(table_name ## _table, fd, query); \
        } \

diff --git a/mood.c b/mood.c
index 13b5b1807a7e2705ff2a8e28561550274371150a..a98f68b2e44c997843148a0400d84d3ba02710be 100644 (file)
--- a/mood.c
+++ b/mood.c
@@ -432,8 +432,10 @@ out:
  *
  * \param fd The afs socket.
  * \param query Unused.
+ *
+ * \return Currently this function always returns zero.
  */
-void mood_check_callback(int fd, __a_unused const struct osl_object *query)
+int mood_check_callback(int fd, __a_unused const struct osl_object *query)
 {
        struct para_buffer pb = {
                .max_size = shm_get_shmmax(),
@@ -448,6 +450,7 @@ void mood_check_callback(int fd, __a_unused const struct osl_object *query)
        osl_rbtree_loop(moods_table, BLOBCOL_ID, &pb,
                check_mood);
        flush_and_free_pb(&pb);
+       return 0;
 }
 
 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)

diff --git a/mood.h b/mood.h
index 2630ba1607fec7e8467ea9a7baca8b5ab263315f..4ea10ef8b988caf5b9e3771a8cb890970ae46cde 100644 (file)
--- a/mood.h
+++ b/mood.h
@@ -8,4 +8,4 @@
 
 int change_current_mood(char *mood_name);
 void close_current_mood(void);
-void mood_check_callback(int fd, __a_unused const struct osl_object *query);
+int mood_check_callback(int fd, __a_unused const struct osl_object *query);

diff --git a/playlist.c b/playlist.c
index 2c5b67777e2f0b41671bc436e3ef7b02f83e6740..e3569358fffeac5dd83799ef6cea60a078edf9ee 100644 (file)
--- a/playlist.c
+++ b/playlist.c
@@ -126,8 +126,10 @@ static int check_playlist(struct osl_row *row, void *data)
  *
  * \param fd The afs socket.
  * \param query Unused.
+ *
+ * \return Currently this function always returns zero.
  */
-void playlist_check_callback(int fd, __a_unused const struct osl_object *query)
+int playlist_check_callback(int fd, __a_unused const struct osl_object *query)
 {
        struct para_buffer pb = {
                .max_size = shm_get_shmmax(),
@@ -141,6 +143,7 @@ void playlist_check_callback(int fd, __a_unused const struct osl_object *query)
        osl_rbtree_loop(playlists_table, BLOBCOL_ID, &pb,
                check_playlist);
        flush_and_free_pb(&pb);
+       return 0;
 }
 
 /**