From 27089920577ab0b7e237c4ec6ef2d8bdcea4a5ed Mon Sep 17 00:00:00 2001 From: "Thibault, Daniel" Date: Fri, 27 Jan 2012 14:33:07 -0500 Subject: [PATCH] Document and enforce return values In config_read_session_name(), moved the malloc to the beginning, to avoid the fscanf() loop from trying to write to a NULL In config_add_session_name(), dealt with another snprintf() occurrence Signed-off-by: Daniel U. Thibault Signed-off-by: David Goulet --- src/bin/lttng/commands/create.c | 8 +++---- src/bin/lttng/conf.c | 40 +++++++++++++++++++++++++-------- 2 files changed, 34 insertions(+), 14 deletions(-) diff --git a/src/bin/lttng/commands/create.c b/src/bin/lttng/commands/create.c index 3a2e136e5..99e5daa93 100644 --- a/src/bin/lttng/commands/create.c +++ b/src/bin/lttng/commands/create.c @@ -115,15 +115,14 @@ static int create_session() ret = lttng_create_session(session_name, traces_path); if (ret < 0) { + ret = CMD_ERROR; goto error; } /* Init lttng session config */ ret = config_init(session_name); if (ret < 0) { - if (ret == -1) { - ret = CMD_ERROR; - } + ret = CMD_ERROR; goto error; } @@ -159,11 +158,10 @@ int cmd_create(int argc, const char **argv) while ((opt = poptGetNextOpt(pc)) != -1) { switch (opt) { case OPT_HELP: - usage(stderr); + usage(stdout); goto end; case OPT_LIST_OPTIONS: list_cmd_options(stdout, long_options); - ret = CMD_SUCCESS; goto end; default: usage(stderr); diff --git a/src/bin/lttng/conf.c b/src/bin/lttng/conf.c index cdd264a5d..00991b081 100644 --- a/src/bin/lttng/conf.c +++ b/src/bin/lttng/conf.c @@ -32,7 +32,8 @@ /* * config_get_file_path * - * Return the path with '/CONFIG_FILENAME' added to it. + * Returns the path with '/CONFIG_FILENAME' added to it; + * path will be NULL if an error occurs. */ char *config_get_file_path(char *path) { @@ -50,7 +51,8 @@ char *config_get_file_path(char *path) /* * open_config * - * Return an open FILE pointer to the config file. + * Returns an open FILE pointer to the config file; + * on error, NULL is returned. */ static FILE *open_config(char *path, const char *mode) { @@ -77,7 +79,9 @@ error: /* * create_config_file * - * Create the empty config file a the path. + * Creates the empty config file at the path. + * On success, returns 0; + * on error, returns -1. */ static int create_config_file(char *path) { @@ -101,6 +105,8 @@ error: * write_config * * Append data to the config file in file_path + * On success, returns 0; + * on error, returns -1. */ static int write_config(char *file_path, size_t size, char *data) { @@ -116,7 +122,7 @@ static int write_config(char *file_path, size_t size, char *data) /* Write session name into config file */ len = fwrite(data, size, 1, fp); - if (len < 1) { + if (len != 1) { ret = -1; } fclose(fp); @@ -127,7 +133,7 @@ end: /* * config_get_default_path * - * Return the HOME directory path. Caller MUST NOT free(3) the return pointer. + * Returns the HOME directory path. Caller MUST NOT free(3) the return pointer. */ char *config_get_default_path(void) { @@ -137,7 +143,7 @@ char *config_get_default_path(void) /* * config_destroy * - * Destroy directory config and file config. + * Destroys directory config and file config. */ void config_destroy(char *path) { @@ -160,7 +166,9 @@ void config_destroy(char *path) /* * config_read_session_name * - * Return sesson name from the config file. + * Returns the session name from the config file. + * The caller is responsible for freeing the returned string. + * On error, NULL is returned. */ char *config_read_session_name(char *path) { @@ -168,6 +176,12 @@ char *config_read_session_name(char *path) FILE *fp; char var[NAME_MAX], *session_name; + session_name = malloc(NAME_MAX); + if (session_name == NULL) { + ERR("Out of memory"); + goto error; + } + fp = open_config(path, "r"); if (fp == NULL) { ERR("Can't find valid lttng config %s/.lttngrc", path); @@ -175,7 +189,6 @@ char *config_read_session_name(char *path) goto error; } - session_name = malloc(NAME_MAX); while (!feof(fp)) { if ((ret = fscanf(fp, "%[^'=']=%s\n", var, session_name)) != 2) { if (ret == -1) { @@ -206,14 +219,21 @@ found: * config_add_session_name * * Write session name option to the config file. + * On success, returns 0; + * on error, returns -1. */ int config_add_session_name(char *path, char *name) { int ret; char session_name[NAME_MAX]; + /* + * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small; + * With GNU C >= 2.1, snprintf returns the required size (excluding closing null) + */ ret = snprintf(session_name, NAME_MAX, "session=%s\n", name); - if (ret < 0) { + if ((ret < 0) || (ret >= NAME_MAX)) { + ret = -1; goto error; } ret = write_config(path, ret, session_name); @@ -225,6 +245,8 @@ error: * config_init * * Init configuration directory and file. + * On success, returns 0; + * on error, returns -1. */ int config_init(char *session_name) { -- 2.34.1