* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#define _GNU_SOURCE
#define _LGPL_SOURCE
#include <assert.h>
#include <ctype.h>
#include <grp.h>
#include <pwd.h>
#include <sys/file.h>
-#include <dirent.h>
+#include <unistd.h>
#include <common/common.h>
#include <common/runas.h>
#include <common/compat/getenv.h>
#include <common/compat/string.h>
+#include <common/compat/dirent.h>
+#include <lttng/constant.h>
#include "utils.h"
#include "defaults.h"
+#include "time.h"
/*
* Return a partial realpath(3) of the path even if the full path does not
/* 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
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
}
} 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;
error:
free(resolved_path);
free(cut_path);
+ free(try_path);
+ if (try_path_prev != try_path) {
+ free(try_path_prev);
+ }
return NULL;
}
+static
+int expand_double_slashes_dot_and_dotdot(char *path)
+{
+ size_t expanded_path_len, path_len;
+ const char *curr_char, *path_last_char, *next_slash, *prev_slash;
+
+ path_len = strlen(path);
+ path_last_char = &path[path_len];
+
+ if (path_len == 0) {
+ goto error;
+ }
+
+ expanded_path_len = 0;
+
+ /* We iterate over the provided path to expand the "//", "../" and "./" */
+ for (curr_char = path; curr_char <= path_last_char; curr_char = next_slash + 1) {
+ /* Find the next forward slash. */
+ size_t curr_token_len;
+
+ if (curr_char == path_last_char) {
+ expanded_path_len++;
+ break;
+ }
+
+ next_slash = memchr(curr_char, '/', path_last_char - curr_char);
+ if (next_slash == NULL) {
+ /* Reached the end of the provided path. */
+ next_slash = path_last_char;
+ }
+
+ /* Compute how long is the previous token. */
+ curr_token_len = next_slash - curr_char;
+ switch(curr_token_len) {
+ case 0:
+ /*
+ * The pointer has not move meaning that curr_char is
+ * pointing to a slash. It that case there is no token
+ * to copy, so continue the iteration to find the next
+ * token
+ */
+ continue;
+ case 1:
+ /*
+ * The pointer moved 1 character. Check if that
+ * character is a dot ('.'), if it is: omit it, else
+ * copy the token to the normalized path.
+ */
+ if (curr_char[0] == '.') {
+ continue;
+ }
+ break;
+ case 2:
+ /*
+ * The pointer moved 2 characters. Check if these
+ * characters are double dots ('..'). If that is the
+ * case, we need to remove the last token of the
+ * normalized path.
+ */
+ if (curr_char[0] == '.' && curr_char[1] == '.') {
+ /*
+ * Find the previous path component by
+ * using the memrchr function to find the
+ * previous forward slash and substract that
+ * len to the resulting path.
+ */
+ prev_slash = lttng_memrchr(path, '/', expanded_path_len);
+ /*
+ * If prev_slash is NULL, we reached the
+ * beginning of the path. We can't go back any
+ * further.
+ */
+ if (prev_slash != NULL) {
+ expanded_path_len = prev_slash - path;
+ }
+ continue;
+ }
+ break;
+ default:
+ break;
+ }
+
+ /*
+ * Copy the current token which is neither a '.' nor a '..'.
+ */
+ path[expanded_path_len++] = '/';
+ memcpy(&path[expanded_path_len], curr_char, curr_token_len);
+ expanded_path_len += curr_token_len;
+ }
+
+ if (expanded_path_len == 0) {
+ path[expanded_path_len++] = '/';
+ }
+
+ path[expanded_path_len] = '\0';
+ return 0;
+error:
+ return -1;
+}
+
/*
* Make a full resolution of the given path even if it doesn't exist.
* This function uses the utils_partial_realpath function to resolve
* the responsibility of the caller to free this memory.
*/
LTTNG_HIDDEN
-char *utils_expand_path(const char *path)
+char *_utils_expand_path(const char *path, bool keep_symlink)
{
- char *next, *previous, *slash, *start_path, *absolute_path = NULL;
+ int ret;
+ char *absolute_path = NULL;
char *last_token;
- int is_dot, is_dotdot;
+ bool is_dot, is_dotdot;
/* Safety net */
if (path == NULL) {
}
/* Allocate memory for the absolute_path */
- absolute_path = zmalloc(PATH_MAX);
+ absolute_path = zmalloc(LTTNG_PATH_MAX);
if (absolute_path == NULL) {
PERROR("zmalloc expand path");
goto error;
}
- /*
- * If the path is not already absolute nor explicitly relative,
- * consider we're in the current directory
- */
- if (*path != '/' && strncmp(path, "./", 2) != 0 &&
- strncmp(path, "../", 3) != 0) {
- snprintf(absolute_path, PATH_MAX, "./%s", path);
- /* Else, we just copy the path */
- } else {
- strncpy(absolute_path, path, PATH_MAX);
- }
-
- /* Resolve partially our path */
- absolute_path = utils_partial_realpath(absolute_path,
- absolute_path, PATH_MAX);
-
- /* As long as we find '/./' in the working_path string */
- while ((next = strstr(absolute_path, "/./"))) {
-
- /* We prepare the start_path not containing it */
- start_path = lttng_strndup(absolute_path, next - absolute_path);
- if (!start_path) {
- PERROR("lttng_strndup");
+ if (path[0] == '/') {
+ ret = lttng_strncpy(absolute_path, path, LTTNG_PATH_MAX);
+ if (ret) {
+ ERR("Path exceeds maximal size of %i bytes", LTTNG_PATH_MAX);
goto error;
}
- /* And we concatenate it with the part after this string */
- snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 2);
-
- free(start_path);
- }
+ } else {
+ /*
+ * This is a relative path. We need to get the present working
+ * directory and start the path walk from there.
+ */
+ char current_working_dir[LTTNG_PATH_MAX];
+ char *cwd_ret;
- /* As long as we find '/../' in the working_path string */
- while ((next = strstr(absolute_path, "/../"))) {
- /* We find the last level of directory */
- previous = absolute_path;
- while ((slash = strpbrk(previous, "/")) && slash != next) {
- previous = slash + 1;
+ cwd_ret = getcwd(current_working_dir, sizeof(current_working_dir));
+ if (!cwd_ret) {
+ goto error;
}
-
- /* Then we prepare the start_path not containing it */
- start_path = lttng_strndup(absolute_path, previous - absolute_path);
- if (!start_path) {
- PERROR("lttng_strndup");
+ /*
+ * Get the number of character in the CWD and allocate an array
+ * to can hold it and the path provided by the caller.
+ */
+ ret = snprintf(absolute_path, LTTNG_PATH_MAX, "%s/%s",
+ current_working_dir, path);
+ if (ret >= LTTNG_PATH_MAX) {
+ ERR("Concatenating current working directory %s and path %s exceeds maximal size of %i bytes",
+ current_working_dir, path, LTTNG_PATH_MAX);
goto error;
}
+ }
- /* And we concatenate it with the part after the '/../' */
- snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 4);
-
- /* We can free the memory used for the start path*/
- free(start_path);
-
- /* Then we verify for symlinks using partial_realpath */
+ if (keep_symlink) {
+ /* Resolve partially our path */
absolute_path = utils_partial_realpath(absolute_path,
- absolute_path, PATH_MAX);
+ absolute_path, LTTNG_PATH_MAX);
+ }
+
+ ret = expand_double_slashes_dot_and_dotdot(absolute_path);
+ if (ret) {
+ goto error;
}
/* Identify the last token */
free(absolute_path);
return NULL;
}
+LTTNG_HIDDEN
+char *utils_expand_path(const char *path)
+{
+ return _utils_expand_path(path, true);
+}
+LTTNG_HIDDEN
+char *utils_expand_path_keep_symlink(const char *path)
+{
+ return _utils_expand_path(path, false);
+}
/*
* Create a pipe in dst.
*/
goto error;
}
- ret = fprintf(fp, "%d\n", pid);
+ ret = fprintf(fp, "%d\n", (int) pid);
if (ret < 0) {
PERROR("fprintf pid file");
goto error;
if (fclose(fp)) {
PERROR("fclose");
}
- DBG("Pid %d written in file %s", pid, filepath);
+ DBG("Pid %d written in file %s", (int) pid, filepath);
ret = 0;
error:
return ret;
{
int ret;
int fd;
+ struct flock lock;
assert(filepath);
- fd = open(filepath, O_CREAT,
- O_WRONLY | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+ 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);
- ret = -1;
+ fd = -1;
goto error;
}
* already a process using the same lock file running
* and we should exit.
*/
- ret = flock(fd, LOCK_EX | LOCK_NB);
- if (ret) {
+ 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)) {
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.
*
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);
}
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;
}
}
- 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:
strncpy(path, path_name_suffix, PATH_MAX - 1);
path[PATH_MAX - 1] = '\0';
} else {
- strncpy(path, full_path, PATH_MAX - 1);
+ ret = lttng_strncpy(path, full_path, PATH_MAX);
+ if (ret) {
+ ERR("Failed to copy stream file name");
+ goto error_free_suffix;
+ }
}
path[PATH_MAX - 1] = '\0';
ret = 0;
goto error;
}
- flags = O_WRONLY | O_CREAT | O_TRUNC;
+ /*
+ * 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;
{
int ret;
- assert(new_count);
assert(stream_fd);
ret = close(out_fd);
PERROR("Closing tracefile");
goto error;
}
+ *stream_fd = -1;
if (count > 0) {
/*
* 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;
}
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
#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)
{
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.
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.
*
PERROR("Cannot open '%s' path", path);
return -1;
}
- dir_fd = dirfd(dir);
+ dir_fd = lttng_dirfd(dir);
if (dir_fd < 0) {
- PERROR("dirfd");
+ PERROR("lttng_dirfd");
return -1;
}
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)",
}
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;
+}