X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng%2Fconf.c;h=4079d6ed9421273680d102d4bc9cf9353534dfb6;hp=cdd264a5d11a3246e4430a3acce5cf354a68e731;hb=ce0b1d61919f37517a6212f7af2afe0fa1b1dcb0;hpb=00f368638a00aa0a823d5ed8b077af74339b687b diff --git a/src/bin/lttng/conf.c b/src/bin/lttng/conf.c index cdd264a5d..4079d6ed9 100644 --- a/src/bin/lttng/conf.c +++ b/src/bin/lttng/conf.c @@ -1,22 +1,11 @@ /* - * Copyright (c) 2011 David Goulet + * Copyright (C) 2011 David Goulet * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * as published by the Free Software Foundation; only version 2 - * of the License. + * SPDX-License-Identifier: GPL-2.0-only * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ -#define _GNU_SOURCE +#define _LGPL_SOURCE #include #include #include @@ -25,16 +14,17 @@ #include #include -#include +#include +#include +#include #include "conf.h" /* - * 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) +char *config_get_file_path(const char *path) { int ret; char *file_path; @@ -42,17 +32,17 @@ char *config_get_file_path(char *path) ret = asprintf(&file_path, "%s/%s", path, CONFIG_FILENAME); if (ret < 0) { ERR("Fail allocating config file path"); + file_path = NULL; } return file_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) +static FILE *open_config(const char *path, const char *mode) { FILE *fp = NULL; char *file_path; @@ -68,18 +58,16 @@ static FILE *open_config(char *path, const char *mode) } error: - if (file_path) { - free(file_path); - } + free(file_path); return fp; } /* - * 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) +static int create_config_file(const char *path) { int ret; FILE *fp; @@ -98,11 +86,11 @@ error: } /* - * write_config - * - * Append data to the config file in file_path + * 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) +static int write_config(const char *file_path, size_t size, char *data) { FILE *fp; size_t len; @@ -116,30 +104,20 @@ 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); + if (fclose(fp)) { + PERROR("close write_config"); + } end: return ret; } /* - * config_get_default_path - * - * Return the HOME directory path. Caller MUST NOT free(3) the return pointer. + * Destroys directory config and file config. */ -char *config_get_default_path(void) -{ - return getenv("HOME"); -} - -/* - * config_destroy - * - * Destroy directory config and file config. - */ -void config_destroy(char *path) +void config_destroy(const char *path) { int ret; char *config_path; @@ -149,35 +127,74 @@ void config_destroy(char *path) return; } + if (!config_exists(config_path)) { + goto end; + } + + DBG("Removing %s\n", config_path); ret = remove(config_path); if (ret < 0) { - perror("remove config file"); + PERROR("remove config file"); } - +end: free(config_path); } /* - * config_read_session_name - * - * Return sesson name from the config file. + * Destroys the default config + */ +void config_destroy_default(void) +{ + const char *path = utils_get_home_dir(); + if (path == NULL) { + return; + } + config_destroy(path); +} + +/* + * Returns 1 if config exists, 0 otherwise */ -char *config_read_session_name(char *path) +int config_exists(const char *path) { int ret; + struct stat info; + + ret = stat(path, &info); + if (ret < 0) { + return 0; + } + return S_ISREG(info.st_mode) || S_ISDIR(info.st_mode); +} + +static +int _config_read_session_name(const char *path, char **name) +{ + int ret = 0; FILE *fp; char var[NAME_MAX], *session_name; +#if (NAME_MAX == 255) +#define NAME_MAX_SCANF_IS_A_BROKEN_API "254" +#endif + + session_name = zmalloc(NAME_MAX); + if (session_name == NULL) { + ret = -ENOMEM; + ERR("Out of memory"); + goto error; + } + fp = open_config(path, "r"); if (fp == NULL) { - ERR("Can't find valid lttng config %s/.lttngrc", path); - MSG("Did you create a session? (lttng create )"); + ret = -ENOENT; goto error; } - session_name = malloc(NAME_MAX); while (!feof(fp)) { - if ((ret = fscanf(fp, "%[^'=']=%s\n", var, session_name)) != 2) { + if ((ret = fscanf(fp, "%" NAME_MAX_SCANF_IS_A_BROKEN_API + "[^'=']=%" NAME_MAX_SCANF_IS_A_BROKEN_API "s\n", + var, session_name)) != 2) { if (ret == -1) { ERR("Missing session=NAME in config file."); goto error_close; @@ -191,29 +208,75 @@ char *config_read_session_name(char *path) } error_close: - fclose(fp); - + if (fclose(fp) < 0) { + PERROR("close config read session name"); + } error: - return NULL; - + free(session_name); + return ret; found: - fclose(fp); - return session_name; - + *name = session_name; + if (fclose(fp) < 0) { + PERROR("close config read session name found"); + } + return ret; } /* - * config_add_session_name + * Returns the session name from the config file. * - * Write session name option to the config file. + * The caller is responsible for freeing the returned string. + * On error, NULL is returned. */ -int config_add_session_name(char *path, char *name) +char *config_read_session_name(const char *path) { int ret; - char session_name[NAME_MAX]; + char *name = NULL; + + ret = _config_read_session_name(path, &name); + if (ret == -ENOENT) { + const char *home_dir = utils_get_home_dir(); - ret = snprintf(session_name, NAME_MAX, "session=%s\n", name); + ERR("Can't find valid lttng config %s/.lttngrc", home_dir); + MSG("Did you create a session? (lttng create )"); + } + + return name; +} + +/* + * Returns the session name from the config file. (no warnings/errors emitted) + * + * The caller is responsible for freeing the returned string. + * On error, NULL is returned. + */ +char *config_read_session_name_quiet(const char *path) +{ + char *name = NULL; + + (void) _config_read_session_name(path, &name); + return name; +} + +/* + * Write session name option to the config file. + * On success, returns 0; + * on error, returns -1. + */ +int config_add_session_name(const char *path, const char *name) +{ + int ret; + const char *attr = "session="; + /* Max name len accepted plus attribute's len and the NULL byte. */ + char session_name[NAME_MAX + strlen(attr) + 1]; + + /* + * 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, sizeof(session_name), "%s%s\n", attr, name); if (ret < 0) { + ret = -1; goto error; } ret = write_config(path, ret, session_name); @@ -222,16 +285,16 @@ error: } /* - * config_init - * - * Init configuration directory and file. + * Init configuration directory and file. + * On success, returns 0; + * on error, returns -1. */ -int config_init(char *session_name) +int config_init(const char *session_name) { int ret; - char *path; + const char *path; - path = config_get_default_path(); + path = utils_get_home_dir(); if (path == NULL) { ret = -1; goto error;