Fix: PERROR spam when `tracing` group does not exist

[lttng-tools.git] / src / common / utils.c

diff --git a/src/common/utils.c b/src/common/utils.c
index d9bacad0e7a7f32dd660e2d6db28b754b7545066..2a20e5a8c4ab4cca1557ca917cfa2de02defd905 100644 (file)
--- a/src/common/utils.c
+++ b/src/common/utils.c
@@ -7,6 +7,7 @@
  *
  */
 
+#include "common/macros.h"
 #define _LGPL_SOURCE
 #include <assert.h>
 #include <ctype.h>
@@ -50,6 +51,9 @@
 #error MAX_NAME_LEN_SCANF_IS_A_BROKEN_API must be updated to match (PROC_MEMINFO_FIELD_MAX_NAME_LEN - 1)
 #endif
 
+#define FALLBACK_USER_BUFLEN 16384
+#define FALLBACK_GROUP_BUFLEN 16384
+
 /*
  * Return a partial realpath(3) of the path even if the full path does not
  * exist. For instance, with /tmp/test1/test2/test3, if test2/ does not exist
@@ -290,7 +294,7 @@ int expand_double_slashes_dot_and_dotdot(char *path)
                 * Copy the current token which is neither a '.' nor a '..'.
                 */
                path[expanded_path_len++] = '/';
-               memcpy(&path[expanded_path_len], curr_char, curr_token_len);
+               memmove(&path[expanded_path_len], curr_char, curr_token_len);
                expanded_path_len += curr_token_len;
        }
 
@@ -537,6 +541,7 @@ void utils_close_pipe(int *src)
                if (ret) {
                        PERROR("close pipe");
                }
+               src[i] = -1;
        }
 }
 
@@ -731,7 +736,7 @@ int utils_stream_file_path(const char *path_name, const char *file_name,
                char *out_stream_path, size_t stream_path_len)
 {
        int ret;
-        char count_str[MAX_INT_DEC_LEN(count) + 1] = {};
+       char count_str[MAX_INT_DEC_LEN(count) + 1] = {};
        const char *path_separator;
 
        if (path_name && (path_name[0] == '\0' ||
@@ -749,7 +754,7 @@ int utils_stream_file_path(const char *path_name, const char *file_name,
                assert(ret > 0 && ret < sizeof(count_str));
        }
 
-        ret = snprintf(out_stream_path, stream_path_len, "%s%s%s%s%s",
+       ret = snprintf(out_stream_path, stream_path_len, "%s%s%s%s%s",
                        path_name, path_separator, file_name, count_str,
                        suffix);
        if (ret < 0 || ret >= stream_path_len) {
@@ -1269,8 +1274,14 @@ int utils_get_group_id(const char *name, bool warn, gid_t *gid)
                }
        }
        if (ret) {
-               PERROR("Failed to get group file entry for group name \"%s\"",
-                               name);
+               if (ret == ESRCH) {
+                       DBG("Could not find group file entry for group name '%s'",
+                                       name);
+               } else {
+                       PERROR("Failed to get group file entry for group name '%s'",
+                                       name);
+               }
+
                ret = -1;
                goto error;
        }
@@ -1527,3 +1538,134 @@ int utils_change_working_directory(const char *path)
 end:
        return ret;
 }
+
+LTTNG_HIDDEN
+enum lttng_error_code utils_user_id_from_name(const char *user_name, uid_t *uid)
+{
+       struct passwd p, *pres;
+       int ret;
+       enum lttng_error_code ret_val = LTTNG_OK;
+       char *buf = NULL;
+       ssize_t buflen;
+
+       buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
+       if (buflen < 0) {
+               buflen = FALLBACK_USER_BUFLEN;
+       }
+
+       buf = zmalloc(buflen);
+       if (!buf) {
+               ret_val = LTTNG_ERR_NOMEM;
+               goto end;
+       }
+
+       for (;;) {
+               ret = getpwnam_r(user_name, &p, buf, buflen, &pres);
+               switch (ret) {
+               case EINTR:
+                       continue;
+               case ERANGE:
+                       buflen *= 2;
+                       free(buf);
+                       buf = zmalloc(buflen);
+                       if (!buf) {
+                               ret_val = LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+                       continue;
+               default:
+                       goto end_loop;
+               }
+       }
+end_loop:
+
+       switch (ret) {
+       case 0:
+               if (pres == NULL) {
+                       ret_val = LTTNG_ERR_USER_NOT_FOUND;
+               } else {
+                       *uid = p.pw_uid;
+                       DBG("Lookup of tracker UID/VUID: name '%s' maps to uid %" PRId64,
+                                       user_name, (int64_t) *uid);
+                       ret_val = LTTNG_OK;
+               }
+               break;
+       case ENOENT:
+       case ESRCH:
+       case EBADF:
+       case EPERM:
+               ret_val = LTTNG_ERR_USER_NOT_FOUND;
+               break;
+       default:
+               ret_val = LTTNG_ERR_NOMEM;
+       }
+end:
+       free(buf);
+       return ret_val;
+}
+
+LTTNG_HIDDEN
+enum lttng_error_code utils_group_id_from_name(
+               const char *group_name, gid_t *gid)
+{
+       struct group g, *gres;
+       int ret;
+       enum lttng_error_code ret_val = LTTNG_OK;
+       char *buf = NULL;
+       ssize_t buflen;
+
+       buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
+       if (buflen < 0) {
+               buflen = FALLBACK_GROUP_BUFLEN;
+       }
+
+       buf = zmalloc(buflen);
+       if (!buf) {
+               ret_val = LTTNG_ERR_NOMEM;
+               goto end;
+       }
+
+       for (;;) {
+               ret = getgrnam_r(group_name, &g, buf, buflen, &gres);
+               switch (ret) {
+               case EINTR:
+                       continue;
+               case ERANGE:
+                       buflen *= 2;
+                       free(buf);
+                       buf = zmalloc(buflen);
+                       if (!buf) {
+                               ret_val = LTTNG_ERR_NOMEM;
+                               goto end;
+                       }
+                       continue;
+               default:
+                       goto end_loop;
+               }
+       }
+end_loop:
+
+       switch (ret) {
+       case 0:
+               if (gres == NULL) {
+                       ret_val = LTTNG_ERR_GROUP_NOT_FOUND;
+               } else {
+                       *gid = g.gr_gid;
+                       DBG("Lookup of tracker GID/GUID: name '%s' maps to gid %" PRId64,
+                                       group_name, (int64_t) *gid);
+                       ret_val = LTTNG_OK;
+               }
+               break;
+       case ENOENT:
+       case ESRCH:
+       case EBADF:
+       case EPERM:
+               ret_val = LTTNG_ERR_GROUP_NOT_FOUND;
+               break;
+       default:
+               ret_val = LTTNG_ERR_NOMEM;
+       }
+end:
+       free(buf);
+       return ret_val;
+}