X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Futils.c;h=004cd8f0d1dcee02aa4b22a4e7f5c6f84a4618f7;hp=9821815ba06298dfbb7e76de02bbc385b9d49d0d;hb=7010c0332387eea98b52f301458d481f151840a6;hpb=68e6efddb6a27675d6cf15161d7b0101154b56ac diff --git a/src/common/utils.c b/src/common/utils.c index 9821815ba..004cd8f0d 100644 --- a/src/common/utils.c +++ b/src/common/utils.c @@ -17,22 +17,27 @@ * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ -#define _GNU_SOURCE +#define _LGPL_SOURCE #include #include #include #include #include -#include #include #include #include #include #include #include +#include +#include #include #include +#include +#include +#include +#include #include "utils.h" #include "defaults.h" @@ -51,7 +56,7 @@ LTTNG_HIDDEN char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) { - char *cut_path, *try_path = NULL, *try_path_prev = NULL; + char *cut_path = NULL, *try_path = NULL, *try_path_prev = NULL; const char *next, *prev, *end; /* Safety net */ @@ -78,6 +83,8 @@ char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) /* Resolve the canonical path of the first part of the path */ while (try_path != NULL && next != end) { + char *try_path_buf = NULL; + /* * If there is not any '/' left, we want to try with * the full path @@ -88,11 +95,22 @@ char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) } /* Cut the part we will be trying to resolve */ - cut_path = strndup(path, next - path); + cut_path = lttng_strndup(path, next - path); + if (cut_path == NULL) { + PERROR("lttng_strndup"); + goto error; + } + + try_path_buf = zmalloc(LTTNG_PATH_MAX); + if (!try_path_buf) { + PERROR("zmalloc"); + goto error; + } /* Try to resolve this part */ - try_path = realpath((char *)cut_path, NULL); + try_path = realpath((char *) cut_path, try_path_buf); if (try_path == NULL) { + free(try_path_buf); /* * There was an error, we just want to be assured it * is linked to an unexistent directory, if it's another @@ -109,6 +127,7 @@ char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) } } else { /* Save the place we are before trying the next step */ + try_path_buf = NULL; free(try_path_prev); try_path_prev = try_path; prev = next; @@ -116,7 +135,8 @@ char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) /* Free the allocated memory */ free(cut_path); - }; + cut_path = NULL; + } /* Allocate memory for the resolved path if necessary */ if (resolved_path == NULL) { @@ -142,6 +162,10 @@ char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) * path are pointers for the same memory space */ cut_path = strdup(prev); + if (cut_path == NULL) { + PERROR("strdup"); + goto error; + } /* Concatenate the strings */ snprintf(resolved_path, size, "%s%s", try_path_prev, cut_path); @@ -149,6 +173,8 @@ char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) /* Free the allocated memory */ free(cut_path); free(try_path_prev); + cut_path = NULL; + try_path_prev = NULL; /* * Else, we just copy the path in our resolved_path to * return it as is @@ -162,6 +188,11 @@ char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) error: free(resolved_path); + free(cut_path); + free(try_path); + if (try_path_prev != try_path) { + free(try_path_prev); + } return NULL; } @@ -214,8 +245,11 @@ char *utils_expand_path(const char *path) while ((next = strstr(absolute_path, "/./"))) { /* We prepare the start_path not containing it */ - start_path = strndup(absolute_path, next - absolute_path); - + start_path = lttng_strndup(absolute_path, next - absolute_path); + if (!start_path) { + PERROR("lttng_strndup"); + goto error; + } /* And we concatenate it with the part after this string */ snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 2); @@ -231,7 +265,11 @@ char *utils_expand_path(const char *path) } /* Then we prepare the start_path not containing it */ - start_path = strndup(absolute_path, previous - absolute_path); + start_path = lttng_strndup(absolute_path, previous - absolute_path); + if (!start_path) { + PERROR("lttng_strndup"); + goto error; + } /* And we concatenate it with the part after the '/../' */ snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 4); @@ -457,24 +495,142 @@ int utils_create_pid_file(pid_t pid, const char *filepath) goto error; } - ret = fprintf(fp, "%d\n", pid); + ret = fprintf(fp, "%d\n", (int) pid); if (ret < 0) { PERROR("fprintf pid file"); + goto error; } - fclose(fp); - DBG("Pid %d written in file %s", pid, filepath); + if (fclose(fp)) { + PERROR("fclose"); + } + DBG("Pid %d written in file %s", (int) pid, filepath); + ret = 0; error: return ret; } /* - * Recursively create directory using the given path and mode. + * 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; + struct flock lock; + + assert(filepath); + + memset(&lock, 0, sizeof(lock)); + fd = open(filepath, O_CREAT | O_WRONLY, S_IRUSR | S_IWUSR | + S_IRGRP | S_IWGRP); + if (fd < 0) { + PERROR("open lock file %s", filepath); + fd = -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. + */ + lock.l_whence = SEEK_SET; + lock.l_type = F_WRLCK; + + ret = fcntl(fd, F_SETLK, &lock); + if (ret == -1) { + PERROR("fcntl lock file"); + ERR("Could not get lock file %s, another instance is running.", + filepath); + if (close(fd)) { + PERROR("close lock file"); + } + fd = ret; + goto error; + } + +error: + return fd; +} + +/* + * On some filesystems (e.g. nfs), mkdir will validate access rights before + * checking for the existence of the path element. This means that on a setup + * where "/home/" is a mounted NFS share, and running as an unpriviledged user, + * recursively creating a path of the form "/home/my_user/trace/" will fail with + * EACCES on mkdir("/home", ...). + * + * Performing a stat(...) on the path to check for existence allows us to + * work around this behaviour. + */ +static +int mkdir_check_exists(const char *path, mode_t mode) +{ + int ret = 0; + struct stat st; + + ret = stat(path, &st); + if (ret == 0) { + if (S_ISDIR(st.st_mode)) { + /* Directory exists, skip. */ + goto end; + } else { + /* Exists, but is not a directory. */ + errno = ENOTDIR; + ret = -1; + goto end; + } + } + + /* + * Let mkdir handle other errors as the caller expects mkdir + * semantics. + */ + ret = mkdir(path, mode); +end: + return ret; +} + +/* + * Create directory using the given path and mode. * * On success, return 0 else a negative error code. */ LTTNG_HIDDEN -int utils_mkdir_recursive(const char *path, mode_t mode) +int utils_mkdir(const char *path, mode_t mode, int uid, int gid) +{ + int ret; + + if (uid < 0 || gid < 0) { + ret = mkdir_check_exists(path, mode); + } else { + ret = run_as_mkdir(path, mode, uid, gid); + } + if (ret < 0) { + if (errno != EEXIST) { + PERROR("mkdir %s, uid %d, gid %d", path ? path : "NULL", + uid, gid); + } else { + ret = 0; + } + } + + return ret; +} + +/* + * Internal version of mkdir_recursive. Runs as the current user. + * Don't call directly; use utils_mkdir_recursive(). + * + * This function is ominously marked as "unsafe" since it should only + * be called by a caller that has transitioned to the uid and gid under which + * the directory creation should occur. + */ +LTTNG_HIDDEN +int _utils_mkdir_recursive_unsafe(const char *path, mode_t mode) { char *p, tmp[PATH_MAX]; size_t len; @@ -504,9 +660,9 @@ int utils_mkdir_recursive(const char *path, mode_t mode) ret = -1; goto error; } - ret = mkdir(tmp, mode); + ret = mkdir_check_exists(tmp, mode); if (ret < 0) { - if (errno != EEXIST) { + if (errno != EACCES) { PERROR("mkdir recursive"); ret = -errno; goto error; @@ -516,14 +672,10 @@ int utils_mkdir_recursive(const char *path, mode_t mode) } } - ret = mkdir(tmp, mode); + ret = mkdir_check_exists(tmp, mode); if (ret < 0) { - if (errno != EEXIST) { - PERROR("mkdir recursive last piece"); - ret = -errno; - } else { - ret = 0; - } + PERROR("mkdir recursive last element"); + ret = -errno; } error: @@ -531,20 +683,44 @@ error: } /* - * Create the stream tracefile on disk. + * Recursively create directory using the given path and mode, under the + * provided uid and gid. * - * Return 0 on success or else a negative value. + * On success, return 0 else a negative error code. */ LTTNG_HIDDEN -int utils_create_stream_file(const char *path_name, char *file_name, uint64_t size, - uint64_t count, int uid, int gid, char *suffix) +int utils_mkdir_recursive(const char *path, mode_t mode, int uid, int gid) { - int ret, out_fd, flags, mode; - char full_path[PATH_MAX], *path_name_suffix = NULL, *path; - char *extra = NULL; + int ret; - assert(path_name); - assert(file_name); + if (uid < 0 || gid < 0) { + /* Run as current user. */ + ret = _utils_mkdir_recursive_unsafe(path, mode); + } else { + ret = run_as_mkdir_recursive(path, mode, uid, gid); + } + if (ret < 0) { + PERROR("mkdir %s, uid %d, gid %d", path ? path : "NULL", + uid, gid); + } + + return ret; +} + +/* + * path is the output parameter. It needs to be PATH_MAX len. + * + * Return 0 on success or else a negative value. + */ +static int utils_stream_file_name(char *path, + const char *path_name, const char *file_name, + uint64_t size, uint64_t count, + const char *suffix) +{ + int ret; + char full_path[PATH_MAX]; + char *path_name_suffix = NULL; + char *extra = NULL; ret = snprintf(full_path, sizeof(full_path), "%s/%s", path_name, file_name); @@ -567,8 +743,8 @@ int utils_create_stream_file(const char *path_name, char *file_name, uint64_t si } /* - * If we split the trace in multiple files, we have to add the count at the - * end of the tracefile name + * If we split the trace in multiple files, we have to add the count at + * the end of the tracefile name. */ if (extra) { ret = asprintf(&path_name_suffix, "%s%s", full_path, extra); @@ -576,31 +752,86 @@ int utils_create_stream_file(const char *path_name, char *file_name, uint64_t si PERROR("Allocating path name with extra string"); goto error_free_suffix; } - path = path_name_suffix; + strncpy(path, path_name_suffix, PATH_MAX - 1); + path[PATH_MAX - 1] = '\0'; } else { - path = full_path; + strncpy(path, full_path, PATH_MAX - 1); } + path[PATH_MAX - 1] = '\0'; + ret = 0; - flags = O_WRONLY | O_CREAT | O_TRUNC; + free(path_name_suffix); +error_free_suffix: + free(extra); +error: + return ret; +} + +/* + * Create the stream file on disk. + * + * Return 0 on success or else a negative value. + */ +LTTNG_HIDDEN +int utils_create_stream_file(const char *path_name, char *file_name, uint64_t size, + uint64_t count, int uid, int gid, char *suffix) +{ + int ret, flags, mode; + char path[PATH_MAX]; + + ret = utils_stream_file_name(path, path_name, file_name, + size, count, suffix); + if (ret < 0) { + goto error; + } + + /* + * With the session rotation feature on the relay, we might need to seek + * and truncate a tracefile, so we need read and write access. + */ + flags = O_RDWR | O_CREAT | O_TRUNC; /* Open with 660 mode */ mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP; if (uid < 0 || gid < 0) { - out_fd = open(path, flags, mode); + ret = open(path, flags, mode); } else { - out_fd = run_as_open(path, flags, mode, uid, gid); + ret = run_as_open(path, flags, mode, uid, gid); } - if (out_fd < 0) { + if (ret < 0) { PERROR("open stream path %s", path); - goto error_open; } - ret = out_fd; +error: + return ret; +} -error_open: - free(path_name_suffix); -error_free_suffix: - free(extra); +/* + * Unlink the stream tracefile from disk. + * + * Return 0 on success or else a negative value. + */ +LTTNG_HIDDEN +int utils_unlink_stream_file(const char *path_name, char *file_name, uint64_t size, + uint64_t count, int uid, int gid, char *suffix) +{ + int ret; + char path[PATH_MAX]; + + ret = utils_stream_file_name(path, path_name, file_name, + size, count, suffix); + if (ret < 0) { + goto error; + } + if (uid < 0 || gid < 0) { + ret = unlink(path); + } else { + ret = run_as_unlink(path, uid, gid); + } + if (ret < 0) { + goto error; + } error: + DBG("utils_unlink_stream_file %s returns %d", path, ret); return ret; } @@ -620,7 +851,6 @@ int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size, { int ret; - assert(new_count); assert(stream_fd); ret = close(out_fd); @@ -628,15 +858,38 @@ int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size, PERROR("Closing tracefile"); goto error; } + *stream_fd = -1; if (count > 0) { - *new_count = (*new_count + 1) % count; + /* + * In tracefile rotation, for the relay daemon we need + * to unlink the old file if present, because it may + * still be open in reading by the live thread, and we + * need to ensure that we do not overwrite the content + * between get_index and get_packet. Since we have no + * way to verify integrity of the data content compared + * to the associated index, we need to ensure the reader + * has exclusive access to the file content, and that + * the open of the data file is performed in get_index. + * Unlinking the old file rather than overwriting it + * achieves this. + */ + if (new_count) { + *new_count = (*new_count + 1) % count; + } + ret = utils_unlink_stream_file(path_name, file_name, size, + new_count ? *new_count : 0, uid, gid, 0); + if (ret < 0 && errno != ENOENT) { + goto error; + } } else { - (*new_count)++; + if (new_count) { + (*new_count)++; + } } - ret = utils_create_stream_file(path_name, file_name, size, *new_count, - uid, gid, 0); + ret = utils_create_stream_file(path_name, file_name, size, + new_count ? *new_count : 0, uid, gid, 0); if (ret < 0) { goto error; } @@ -748,6 +1001,107 @@ end: return ret; } +/** + * Parse a string that represents a time in human readable format. It + * supports decimal integers suffixed by 's', 'u', 'm', 'us', and 'ms'. + * + * The suffix multiply the integer by: + * 'u'/'us': 1 + * 'm'/'ms': 1000 + * 's': 1000000 + * + * Note that unit-less numbers are assumed to be microseconds. + * + * @param str The string to parse, assumed to be NULL-terminated. + * @param time_us Pointer to a uint64_t that will be filled with the + * resulting time in microseconds. + * + * @return 0 on success, -1 on failure. + */ +LTTNG_HIDDEN +int utils_parse_time_suffix(char const * const str, uint64_t * const time_us) +{ + int ret; + uint64_t base_time; + long multiplier = 1; + const char *str_end; + char *num_end; + + if (!str) { + DBG("utils_parse_time_suffix: received a NULL string."); + ret = -1; + goto end; + } + + /* strtoull will accept a negative number, but we don't want to. */ + if (strchr(str, '-') != NULL) { + DBG("utils_parse_time_suffix: invalid time string, should not contain '-'."); + ret = -1; + goto end; + } + + /* str_end will point to the \0 */ + str_end = str + strlen(str); + errno = 0; + base_time = strtoull(str, &num_end, 10); + if (errno != 0) { + PERROR("utils_parse_time_suffix strtoull on string \"%s\"", str); + ret = -1; + goto end; + } + + if (num_end == str) { + /* strtoull parsed nothing, not good. */ + DBG("utils_parse_time_suffix: strtoull had nothing good to parse."); + ret = -1; + goto end; + } + + /* Check if a prefix is present. */ + switch (*num_end) { + case 'u': + multiplier = 1; + /* Skip another letter in the 'us' case. */ + num_end += (*(num_end + 1) == 's') ? 2 : 1; + break; + case 'm': + multiplier = 1000; + /* Skip another letter in the 'ms' case. */ + num_end += (*(num_end + 1) == 's') ? 2 : 1; + break; + case 's': + multiplier = 1000000; + num_end++; + break; + case '\0': + break; + default: + DBG("utils_parse_time_suffix: invalid suffix."); + ret = -1; + goto end; + } + + /* Check for garbage after the valid input. */ + if (num_end != str_end) { + DBG("utils_parse_time_suffix: Garbage after time string."); + ret = -1; + goto end; + } + + *time_us = base_time * multiplier; + + /* Check for overflow */ + if ((*time_us / multiplier) != base_time) { + DBG("utils_parse_time_suffix: oops, overflow detected."); + ret = -1; + goto end; + } + + ret = 0; +end: + return ret; +} + /* * fls: returns the position of the most significant bit. * Returns 0 if no bit is set, else returns the position of the most @@ -768,6 +1122,59 @@ static inline unsigned int fls_u32(uint32_t x) #define HAS_FLS_U32 #endif +#if defined(__x86_64) +static inline +unsigned int fls_u64(uint64_t x) +{ + long r; + + asm("bsrq %1,%0\n\t" + "jnz 1f\n\t" + "movq $-1,%0\n\t" + "1:\n\t" + : "=r" (r) : "rm" (x)); + return r + 1; +} +#define HAS_FLS_U64 +#endif + +#ifndef HAS_FLS_U64 +static __attribute__((unused)) +unsigned int fls_u64(uint64_t x) +{ + unsigned int r = 64; + + if (!x) + return 0; + + if (!(x & 0xFFFFFFFF00000000ULL)) { + x <<= 32; + r -= 32; + } + if (!(x & 0xFFFF000000000000ULL)) { + x <<= 16; + r -= 16; + } + if (!(x & 0xFF00000000000000ULL)) { + x <<= 8; + r -= 8; + } + if (!(x & 0xF000000000000000ULL)) { + x <<= 4; + r -= 4; + } + if (!(x & 0xC000000000000000ULL)) { + x <<= 2; + r -= 2; + } + if (!(x & 0x8000000000000000ULL)) { + x <<= 1; + r -= 1; + } + return r; +} +#endif + #ifndef HAS_FLS_U32 static __attribute__((unused)) unsigned int fls_u32(uint32_t x) { @@ -814,6 +1221,20 @@ int utils_get_count_order_u32(uint32_t x) return fls_u32(x - 1); } +/* + * Return the minimum order for which x <= (1UL << order). + * Return -1 if x is 0. + */ +LTTNG_HIDDEN +int utils_get_count_order_u64(uint64_t x) +{ + if (!x) { + return -1; + } + + return fls_u64(x - 1); +} + /** * Obtain the value of LTTNG_HOME environment variable, if exists. * Otherwise returns the value of HOME. @@ -822,11 +1243,28 @@ LTTNG_HIDDEN char *utils_get_home_dir(void) { char *val = NULL; - val = getenv(DEFAULT_LTTNG_HOME_ENV_VAR); + struct passwd *pwd; + + val = lttng_secure_getenv(DEFAULT_LTTNG_HOME_ENV_VAR); + if (val != NULL) { + goto end; + } + val = lttng_secure_getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR); if (val != NULL) { - return val; + goto end; + } + + /* Fallback on the password file entry. */ + pwd = getpwuid(getuid()); + if (!pwd) { + goto end; } - return getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR); + val = pwd->pw_dir; + + DBG3("Home directory is '%s'", val); + +end: + return val; } /** @@ -950,12 +1388,158 @@ char *utils_generate_optstring(const struct option *long_options, break; } - optstring[str_pos++] = (char)long_options[i].val; - if (long_options[i].has_arg) { - optstring[str_pos++] = ':'; + if (long_options[i].val != '\0') { + optstring[str_pos++] = (char) long_options[i].val; + if (long_options[i].has_arg) { + optstring[str_pos++] = ':'; + } } } end: return optstring; } + +/* + * Try to remove a hierarchy of empty directories, recursively. Don't unlink + * any file. Try to rmdir any empty directory within the hierarchy. + */ +LTTNG_HIDDEN +int utils_recursive_rmdir(const char *path) +{ + DIR *dir; + size_t path_len; + int dir_fd, ret = 0, closeret, is_empty = 1; + struct dirent *entry; + + /* Open directory */ + dir = opendir(path); + if (!dir) { + PERROR("Cannot open '%s' path", path); + return -1; + } + dir_fd = lttng_dirfd(dir); + if (dir_fd < 0) { + PERROR("lttng_dirfd"); + return -1; + } + + path_len = strlen(path); + while ((entry = readdir(dir))) { + struct stat st; + size_t name_len; + char filename[PATH_MAX]; + + if (!strcmp(entry->d_name, ".") + || !strcmp(entry->d_name, "..")) { + continue; + } + + name_len = strlen(entry->d_name); + if (path_len + name_len + 2 > sizeof(filename)) { + ERR("Failed to remove file: path name too long (%s/%s)", + path, entry->d_name); + continue; + } + if (snprintf(filename, sizeof(filename), "%s/%s", + path, entry->d_name) < 0) { + ERR("Failed to format path."); + continue; + } + + if (stat(filename, &st)) { + PERROR("stat"); + continue; + } + + if (S_ISDIR(st.st_mode)) { + char subpath[PATH_MAX]; + + strncpy(subpath, path, PATH_MAX); + subpath[PATH_MAX - 1] = '\0'; + strncat(subpath, "/", + PATH_MAX - strlen(subpath) - 1); + strncat(subpath, entry->d_name, + PATH_MAX - strlen(subpath) - 1); + if (utils_recursive_rmdir(subpath)) { + is_empty = 0; + } + } else if (S_ISREG(st.st_mode)) { + is_empty = 0; + } else { + ret = -EINVAL; + goto end; + } + } +end: + closeret = closedir(dir); + if (closeret) { + PERROR("closedir"); + } + if (is_empty) { + DBG3("Attempting rmdir %s", path); + ret = rmdir(path); + } + return ret; +} + +LTTNG_HIDDEN +int utils_truncate_stream_file(int fd, off_t length) +{ + int ret; + + ret = ftruncate(fd, length); + if (ret < 0) { + PERROR("ftruncate"); + goto end; + } + ret = lseek(fd, length, SEEK_SET); + if (ret < 0) { + PERROR("lseek"); + goto end; + } +end: + return ret; +} + +static const char *get_man_bin_path(void) +{ + char *env_man_path = lttng_secure_getenv(DEFAULT_MAN_BIN_PATH_ENV); + + if (env_man_path) { + return env_man_path; + } + + return DEFAULT_MAN_BIN_PATH; +} + +LTTNG_HIDDEN +int utils_show_help(int section, const char *page_name, + const char *help_msg) +{ + char section_string[8]; + const char *man_bin_path = get_man_bin_path(); + int ret = 0; + + if (help_msg) { + printf("%s", help_msg); + goto end; + } + + /* Section integer -> section string */ + ret = sprintf(section_string, "%d", section); + assert(ret > 0 && ret < 8); + + /* + * Execute man pager. + * + * We provide -M to man here because LTTng-tools can + * be installed outside /usr, in which case its man pages are + * not located in the default /usr/share/man directory. + */ + ret = execlp(man_bin_path, "man", "-M", MANPATH, + section_string, page_name, NULL); + +end: + return ret; +}