X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=src%2Fcommon%2Futils.c;h=8ac143cb20f3779a9112009c5ca6dc795de109e7;hb=e7764d6723a2a21ffe5907f5b4c82770d7a57a25;hp=11018739be9ad9c7e6a83340a2434fdc2fc654c1;hpb=d1f721c52e3810dcb38429cb3beec9f80043aa57;p=lttng-tools.git diff --git a/src/common/utils.c b/src/common/utils.c index 11018739b..8ac143cb2 100644 --- a/src/common/utils.c +++ b/src/common/utils.c @@ -30,15 +30,19 @@ #include #include #include +#include #include #include #include #include #include +#include +#include #include "utils.h" #include "defaults.h" +#include "time.h" /* * Return a partial realpath(3) of the path even if the full path does not @@ -81,6 +85,8 @@ 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 @@ -97,9 +103,16 @@ char *utils_partial_realpath(const char *path, char *resolved_path, size_t size) 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 @@ -116,6 +129,7 @@ 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; @@ -177,6 +191,10 @@ 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; } @@ -512,7 +530,7 @@ int utils_create_lock_file(const char *filepath) S_IRGRP | S_IWGRP); if (fd < 0) { PERROR("open lock file %s", filepath); - ret = -1; + fd = -1; goto error; } @@ -540,6 +558,44 @@ 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. * @@ -551,7 +607,7 @@ int utils_mkdir(const char *path, mode_t mode, int uid, int gid) int ret; if (uid < 0 || gid < 0) { - ret = mkdir(path, mode); + ret = mkdir_check_exists(path, mode); } else { ret = run_as_mkdir(path, mode, uid, gid); } @@ -606,9 +662,9 @@ int _utils_mkdir_recursive_unsafe(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; @@ -618,14 +674,10 @@ int _utils_mkdir_recursive_unsafe(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 element"); - ret = -errno; - } else { - ret = 0; - } + PERROR("mkdir recursive last element"); + ret = -errno; } error: @@ -797,7 +849,6 @@ 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); @@ -805,6 +856,7 @@ 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) { /* @@ -820,18 +872,22 @@ int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size, * Unlinking the old file rather than overwriting it * achieves this. */ - *new_count = (*new_count + 1) % count; - ret = utils_unlink_stream_file(path_name, file_name, - size, *new_count, uid, gid, 0); + 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; } @@ -963,6 +1019,59 @@ 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) { @@ -1009,6 +1118,20 @@ 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. @@ -1081,26 +1204,6 @@ end: return home_dir; } -/* - * Obtain the value of LTTNG_KMOD_PROBES environment variable, if exists. - * Otherwise returns NULL. - */ -LTTNG_HIDDEN -char *utils_get_kmod_probes_list(void) -{ - return lttng_secure_getenv(DEFAULT_LTTNG_KMOD_PROBES); -} - -/* - * Obtain the value of LTTNG_EXTRA_KMOD_PROBES environment variable, if - * exists. Otherwise returns NULL. - */ -LTTNG_HIDDEN -char *utils_get_extra_kmod_probes_list(void) -{ - return lttng_secure_getenv(DEFAULT_LTTNG_EXTRA_KMOD_PROBES); -} - /* * With the given format, fill dst with the time of len maximum siz. * @@ -1129,24 +1232,77 @@ size_t utils_get_current_time_str(const char *format, char *dst, size_t len) } /* - * Return the group ID matching name, else 0 if it cannot be found. + * Return 0 on success and set *gid to the group_ID matching the passed name. + * Else -1 if it cannot be found or an error occurred. */ LTTNG_HIDDEN -gid_t utils_get_group_id(const char *name) +int utils_get_group_id(const char *name, bool warn, gid_t *gid) { - struct group *grp; + static volatile int warn_once; + int ret; + long sys_len; + size_t len; + struct group grp; + struct group *result; + struct lttng_dynamic_buffer buffer; + + /* Get the system limit, if it exists. */ + sys_len = sysconf(_SC_GETGR_R_SIZE_MAX); + if (sys_len == -1) { + len = 1024; + } else { + len = (size_t) sys_len; + } - grp = getgrnam(name); - if (!grp) { - static volatile int warn_once; + lttng_dynamic_buffer_init(&buffer); + ret = lttng_dynamic_buffer_set_size(&buffer, len); + if (ret) { + ERR("Failed to allocate group info buffer"); + ret = -1; + goto error; + } - if (!warn_once) { - WARN("No tracing group detected"); - warn_once = 1; + while ((ret = getgrnam_r(name, &grp, buffer.data, buffer.size, &result)) == ERANGE) { + const size_t new_len = 2 * buffer.size; + + /* Buffer is not big enough, increase its size. */ + if (new_len < buffer.size) { + ERR("Group info buffer size overflow"); + ret = -1; + goto error; } - return 0; + + ret = lttng_dynamic_buffer_set_size(&buffer, new_len); + if (ret) { + ERR("Failed to grow group info buffer to %zu bytes", + new_len); + ret = -1; + goto error; + } + } + if (ret) { + PERROR("Failed to get group file entry for group name \"%s\"", + name); + ret = -1; + goto error; } - return grp->gr_gid; + + /* Group not found. */ + if (!result) { + ret = -1; + goto error; + } + + *gid = result->gr_gid; + ret = 0; + +error: + if (ret && warn && !warn_once) { + WARN("No tracing group detected"); + warn_once = 1; + } + lttng_dynamic_buffer_reset(&buffer); + return ret; } /* @@ -1220,14 +1376,15 @@ int utils_recursive_rmdir(const char *path) path_len = strlen(path); while ((entry = readdir(dir))) { - if (!strcmp(entry->d_name, ".") - || !strcmp(entry->d_name, "..")) - continue; - 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)", @@ -1275,3 +1432,101 @@ end: } return ret; } + +LTTNG_HIDDEN +int utils_truncate_stream_file(int fd, off_t length) +{ + int ret; + off_t lseek_ret; + + ret = ftruncate(fd, length); + if (ret < 0) { + PERROR("ftruncate"); + goto end; + } + lseek_ret = lseek(fd, length, SEEK_SET); + if (lseek_ret < 0) { + PERROR("lseek"); + ret = -1; + 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; +} + +LTTNG_HIDDEN +int timespec_to_ms(struct timespec ts, unsigned long *ms) +{ + unsigned long res, remain_ms; + + if (ts.tv_sec > ULONG_MAX / MSEC_PER_SEC) { + errno = EOVERFLOW; + return -1; /* multiplication overflow */ + } + res = ts.tv_sec * MSEC_PER_SEC; + remain_ms = ULONG_MAX - res; + if (ts.tv_nsec / NSEC_PER_MSEC > remain_ms) { + errno = EOVERFLOW; + return -1; /* addition overflow */ + } + res += ts.tv_nsec / NSEC_PER_MSEC; + *ms = res; + return 0; +} + +LTTNG_HIDDEN +struct timespec timespec_abs_diff(struct timespec t1, struct timespec t2) +{ + uint64_t ts1 = (uint64_t) t1.tv_sec * (uint64_t) NSEC_PER_SEC + + (uint64_t) t1.tv_nsec; + uint64_t ts2 = (uint64_t) t2.tv_sec * (uint64_t) NSEC_PER_SEC + + (uint64_t) t2.tv_nsec; + uint64_t diff = max(ts1, ts2) - min(ts1, ts2); + struct timespec res; + + res.tv_sec = diff / (uint64_t) NSEC_PER_SEC; + res.tv_nsec = diff % (uint64_t) NSEC_PER_SEC; + return res; +}