Introduce utils_parse_time_suffix

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

diff --git a/src/common/utils.c b/src/common/utils.c
index 4d49728c0f47a23cce6eba1bc2f72f11c2c14836..004cd8f0d1dcee02aa4b22a4e7f5c6f84a4618f7 100644 (file)
--- a/src/common/utils.c
+++ b/src/common/utils.c
@@ -528,7 +528,7 @@ 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;
        }
 
@@ -785,7 +785,11 @@ int utils_create_stream_file(const char *path_name, char *file_name, uint64_t si
                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;
 
@@ -997,6 +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
@@ -1202,26 +1307,6 @@ 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.
  *
@@ -1429,11 +1514,17 @@ static const char *get_man_bin_path(void)
 }
 
 LTTNG_HIDDEN
-int utils_show_man_page(int section, const char *page_name)
+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;
+       int ret = 0;
+
+       if (help_msg) {
+               printf("%s", help_msg);
+               goto end;
+       }
 
        /* Section integer -> section string */
        ret = sprintf(section_string, "%d", section);
@@ -1448,5 +1539,7 @@ int utils_show_man_page(int section, const char *page_name)
         */
        ret = execlp(man_bin_path, "man", "-M", MANPATH,
                section_string, page_name, NULL);
+
+end:
        return ret;
 }