X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fcommon%2Futils.c;h=0d60dc251c2e897969b604b79e57ee37b53a17bf;hb=52f740b87344f474ce15e0c9bb4a1ae800f57aac;hp=3a4f850ba66b22f19d78bdbd9dd52e1257d8ba75;hpb=664958450af7685c38cccfc9109d8f5b050e0fd9;p=lttng-tools.git diff --git a/src/common/utils.c b/src/common/utils.c index 3a4f850ba..0d60dc251 100644 --- a/src/common/utils.c +++ b/src/common/utils.c @@ -27,8 +27,9 @@ #include #include #include -#include #include +#include +#include #include #include @@ -178,6 +179,8 @@ LTTNG_HIDDEN char *utils_expand_path(const char *path) { char *next, *previous, *slash, *start_path, *absolute_path = NULL; + char *last_token; + int is_dot, is_dotdot; /* Safety net */ if (path == NULL) { @@ -198,7 +201,7 @@ char *utils_expand_path(const char *path) if (*path != '/' && strncmp(path, "./", 2) != 0 && strncmp(path, "../", 3) != 0) { snprintf(absolute_path, PATH_MAX, "./%s", path); - /* Else, we just copy the path */ + /* Else, we just copy the path */ } else { strncpy(absolute_path, path, PATH_MAX); } @@ -241,6 +244,31 @@ char *utils_expand_path(const char *path) absolute_path, PATH_MAX); } + /* Identify the last token */ + last_token = strrchr(absolute_path, '/'); + + /* Verify that this token is not a relative path */ + is_dotdot = (strcmp(last_token, "/..") == 0); + is_dot = (strcmp(last_token, "/.") == 0); + + /* If it is, take action */ + if (is_dot || is_dotdot) { + /* For both, remove this token */ + *last_token = '\0'; + + /* If it was a reference to parent directory, go back one more time */ + if (is_dotdot) { + last_token = strrchr(absolute_path, '/'); + + /* If there was only one level left, we keep the first '/' */ + if (last_token == absolute_path) { + last_token++; + } + + *last_token = '\0'; + } + } + return absolute_path; error: @@ -440,6 +468,44 @@ error: return ret; } +/* + * Create lock file to the given path and filename. + * Returns the associated file descriptor, -1 on error. + */ +LTTNG_HIDDEN +int utils_create_lock_file(const char *filepath) +{ + int ret; + int fd; + + assert(filepath); + + fd = open(filepath, O_CREAT, + O_WRONLY | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); + if (fd < 0) { + PERROR("open lock file %s", filepath); + ret = -1; + goto error; + } + + /* + * Attempt to lock the file. If this fails, there is + * already a process using the same lock file running + * and we should exit. + */ + ret = flock(fd, LOCK_EX | LOCK_NB); + if (ret) { + WARN("Could not get lock file %s, another instance is running.", + filepath); + close(fd); + fd = ret; + goto error; + } + +error: + return fd; +} + /* * Recursively create directory using the given path and mode. * @@ -621,42 +687,10 @@ error: return ret; } -/** - * Prints the error message corresponding to a regex error code. - * - * @param errcode The error code. - * @param regex The regex object that produced the error code. - */ -static void regex_print_error(int errcode, regex_t *regex) -{ - /* Get length of error message and allocate accordingly */ - size_t length; - char *buffer; - - assert(regex != NULL); - - length = regerror(errcode, regex, NULL, 0); - if (length == 0) { - ERR("regerror returned a length of 0"); - return; - } - - buffer = zmalloc(length); - if (!buffer) { - ERR("regex_print_error: zmalloc failed"); - return; - } - - /* Get and print error message */ - regerror(errcode, regex, buffer, length); - ERR("regex error: %s\n", buffer); - free(buffer); - -} /** * Parse a string that represents a size in human readable format. It - * supports decimal integers suffixed by 'k', 'M' or 'G'. + * supports decimal integers suffixed by 'k', 'K', 'M' or 'G'. * * The suffix multiply the integer by: * 'k': 1024 @@ -664,83 +698,90 @@ static void regex_print_error(int errcode, regex_t *regex) * 'G': 1024^3 * * @param str The string to parse. - * @param size Pointer to a size_t that will be filled with the + * @param size Pointer to a uint64_t that will be filled with the * resulting size. * * @return 0 on success, -1 on failure. */ LTTNG_HIDDEN -int utils_parse_size_suffix(char *str, uint64_t *size) +int utils_parse_size_suffix(const char * const str, uint64_t * const size) { - regex_t regex; int ret; - const int nmatch = 3; - regmatch_t suffix_match, matches[nmatch]; - unsigned long long base_size; + uint64_t base_size; long shift = 0; + const char *str_end; + char *num_end; if (!str) { - return 0; - } - - /* Compile regex */ - ret = regcomp(®ex, "^\\(0x\\)\\{0,1\\}[0-9][0-9]*\\([kKMG]\\{0,1\\}\\)$", 0); - if (ret != 0) { - regex_print_error(ret, ®ex); + DBG("utils_parse_size_suffix: received a NULL string."); ret = -1; goto end; } - /* Match regex */ - ret = regexec(®ex, str, nmatch, matches, 0); - if (ret != 0) { + /* strtoull will accept a negative number, but we don't want to. */ + if (strchr(str, '-') != NULL) { + DBG("utils_parse_size_suffix: invalid size string, should not contain '-'."); ret = -1; - goto free; + goto end; } - /* There is a match ! */ + /* str_end will point to the \0 */ + str_end = str + strlen(str); errno = 0; - base_size = strtoull(str, NULL, 0); + base_size = strtoull(str, &num_end, 0); if (errno != 0) { - PERROR("strtoull"); + PERROR("utils_parse_size_suffix strtoull"); ret = -1; - goto free; - } - - /* Check if there is a suffix */ - suffix_match = matches[2]; - if (suffix_match.rm_eo - suffix_match.rm_so == 1) { - switch (*(str + suffix_match.rm_so)) { - case 'K': - case 'k': - shift = KIBI_LOG2; - break; - case 'M': - shift = MEBI_LOG2; - break; - case 'G': - shift = GIBI_LOG2; - break; - default: - ERR("parse_human_size: invalid suffix"); - ret = -1; - goto free; - } + goto end; + } + + if (num_end == str) { + /* strtoull parsed nothing, not good. */ + DBG("utils_parse_size_suffix: strtoull had nothing good to parse."); + ret = -1; + goto end; + } + + /* Check if a prefix is present. */ + switch (*num_end) { + case 'G': + shift = GIBI_LOG2; + num_end++; + break; + case 'M': /* */ + shift = MEBI_LOG2; + num_end++; + break; + case 'K': + case 'k': + shift = KIBI_LOG2; + num_end++; + break; + case '\0': + break; + default: + DBG("utils_parse_size_suffix: invalid suffix."); + ret = -1; + goto end; + } + + /* Check for garbage after the valid input. */ + if (num_end != str_end) { + DBG("utils_parse_size_suffix: Garbage after size string."); + ret = -1; + goto end; } *size = base_size << shift; /* Check for overflow */ if ((*size >> shift) != base_size) { - ERR("parse_size_suffix: oops, overflow detected."); + DBG("utils_parse_size_suffix: oops, overflow detected."); ret = -1; - goto free; + goto end; } ret = 0; - -free: - regfree(®ex); end: return ret; } @@ -819,11 +860,28 @@ LTTNG_HIDDEN char *utils_get_home_dir(void) { char *val = NULL; + struct passwd *pwd; + val = getenv(DEFAULT_LTTNG_HOME_ENV_VAR); if (val != NULL) { - return val; + goto end; + } + val = getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR); + if (val != NULL) { + goto end; } - return getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR); + + /* Fallback on the password file entry. */ + pwd = getpwuid(getuid()); + if (!pwd) { + goto end; + } + val = pwd->pw_dir; + + DBG3("Home directory is '%s'", val); + +end: + return val; } /* @@ -846,7 +904,7 @@ size_t utils_get_current_time_str(const char *format, char *dst, size_t len) timeinfo = localtime(&rawtime); ret = strftime(dst, len, format, timeinfo); if (ret == 0) { - ERR("Unable to strftime with format %s at dst %p of len %lu", format, + ERR("Unable to strftime with format %s at dst %p of len %zu", format, dst, len); }