* 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;
}
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:
*
* Return 0 on success or else a negative value.
*/
-static int utils_stream_file_name(char *path,
+LTTNG_HIDDEN
+int utils_stream_file_name(char *path,
const char *path_name, const char *file_name,
uint64_t size, uint64_t count,
const char *suffix)
return ret;
}
+LTTNG_HIDDEN
+void utils_stream_file_rotation_get_new_count(uint64_t count,
+ uint64_t *new_count, bool *should_unlink)
+{
+ if (count > 0) {
+ /*
+ * 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;
+ }
+ *should_unlink = true;
+ } else {
+ if (new_count) {
+ (*new_count)++;
+ }
+ *should_unlink = false;
+ }
+}
+
/*
* Change the output tracefile according to the given size and count The
* new_count pointer is set during this operation.
int *stream_fd)
{
int ret;
+ bool should_unlink;
- assert(new_count);
assert(stream_fd);
+ utils_stream_file_rotation_get_new_count(count, new_count,
+ &should_unlink);
+
ret = close(out_fd);
if (ret < 0) {
PERROR("Closing tracefile");
goto error;
}
+ *stream_fd = -1;
- if (count > 0) {
- /*
- * 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.
- */
- *new_count = (*new_count + 1) % count;
- ret = utils_unlink_stream_file(path_name, file_name,
- size, *new_count, uid, gid, 0);
+ if (should_unlink) {
+ 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)++;
}
- 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;
}
#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.
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;
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))) {
+ struct stat st;
+ size_t name_len;
+ char filename[PATH_MAX];
+
if (!strcmp(entry->d_name, ".")
- || !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;
- switch (entry->d_type) {
- case DT_DIR:
- {
+ }
+
+ if (S_ISDIR(st.st_mode)) {
char subpath[PATH_MAX];
strncpy(subpath, path, PATH_MAX);
if (utils_recursive_rmdir(subpath)) {
is_empty = 0;
}
- break;
- }
- case DT_REG:
+ } else if (S_ISREG(st.st_mode)) {
is_empty = 0;
- break;
- default:
+ } else {
ret = -EINVAL;
goto 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_man_page(int section, const char *page_name)
+{
+ char section_string[8];
+ const char *man_bin_path = get_man_bin_path();
+ int ret;
+
+ /* 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);
+ return ret;
+}
+
+LTTNG_HIDDEN
+int utils_change_working_dir(const char *path)
+{
+ int ret;
+
+ assert(path);
+
+ ret = chdir(path);
+ if (ret) {
+ PERROR("Failed to change working directory: %s", path);
+ goto end;
+ }
+
+ /* Check for write access */
+ if (access(path, W_OK)) {
+ if (errno == EACCES) {
+ /*
+ * Do not treat this as an error since the permission
+ * might change in the lifetime of the process
+ */
+ DBG("Working directory is not writable: %s", path);
+ } else {
+ PERROR("access");
+ }
+ }
+
+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;
+}
projects / lttng-tools.git / blobdiff