processes plugin: Support processes with spaces in their names.

… without replacing the space in the process name. This is done by using
an equivalent of strchr() and strrchr() to determine the boundaries of
the second "field".

Change-Id: Id4c1a84c0544554fae05623457d2a7a3e0630db2

diff --git a/src/processes.c b/src/processes.c
index 37e84c5..5e448cf 100644 (file)
--- a/src/processes.c
+++ b/src/processes.c
@@ -880,10 +880,13 @@ int ps_read_process (int pid, procstat_t *ps, char *state)
 
        char *fields[64];
        char  fields_len;
-       char *bufp, *namep;
 
-       int   i;
+       int   buffer_len;
 
+       char *buffer_ptr;
+       size_t name_start_pos;
+       size_t name_end_pos;
+       size_t name_len;
 
        long long unsigned cpu_user_counter;
        long long unsigned cpu_system_counter;
@@ -895,28 +898,48 @@ int ps_read_process (int pid, procstat_t *ps, char *state)
 
        ssnprintf (filename, sizeof (filename), "/proc/%i/stat", pid);
 
-       i = read_file_contents (filename, buffer, sizeof(buffer) - 1);
-       if (i <= 0)
+       buffer_len = read_file_contents (filename,
+                       buffer, sizeof(buffer) - 1);
+       if (buffer_len <= 0)
                return (-1);
-       buffer[i] = 0;
-
-       /* Parse out ps->name while sanitizing any whitespace ( \t\r\n) in
-               the process name before calling strsplit
-        */
-       for (bufp = buffer; *bufp != '\0' && *bufp != '('; bufp++);
-       if (*bufp == '\0' || *(++bufp) == '\0')
+       buffer[buffer_len] = 0;
+
+       /* The name of the process is enclosed in parens. Since the name can
+        * contain parens itself, spaces, numbers and pretty much everything
+        * else, use these to determine the process name. We don't use
+        * strchr(3) and strrchr(3) to avoid pointer arithmetic which would
+        * otherwise be required to determine name_len. */
+       name_start_pos = 0;
+       while ((buffer[name_start_pos] != '(')
+                       && (name_start_pos < buffer_len))
+               name_start_pos++;
+
+       name_end_pos = buffer_len;
+       while ((buffer[name_end_pos] != ')')
+                       && (name_end_pos > 0))
+               name_end_pos--;
+
+       /* Either '(' or ')' is not found or they are in the wrong order.
+        * Anyway, something weird that shouldn't happen ever. */
+       if (name_start_pos >= name_end_pos)
+       {
+               ERROR ("processes plugin: name_start_pos = %zu >= name_end_pos = %zu",
+                               name_start_pos, name_end_pos);
                return (-1);
-       namep = ps->name;
-       while (*bufp != '\0' && *bufp != ')') {
-               *namep++ = *bufp;
-               if (*bufp == ' ' || *bufp == '\t' || *bufp == '\r' || *bufp == '\n')
-                       *bufp = '_';
-               bufp++;
        }
-       *namep = '\0';
 
-       fields_len = strsplit (buffer, fields, STATIC_ARRAY_SIZE (fields));
-       if (fields_len < 24)
+       name_len = (name_end_pos - name_start_pos) - 1;
+       if (name_len >= sizeof (ps->name))
+               name_len = sizeof (ps->name) - 1;
+
+       sstrncpy (ps->name, &buffer[name_start_pos + 1], name_len + 1);
+
+       if ((buffer_len - name_end_pos) < 2)
+               return (-1);
+       buffer_ptr = &buffer[name_end_pos + 2];
+
+       fields_len = strsplit (buffer_ptr, fields, STATIC_ARRAY_SIZE (fields));
+       if (fields_len < 22)
        {
                DEBUG ("processes plugin: ps_read_process (pid = %i):"
                                " `%s' has only %i fields..",
@@ -924,7 +947,7 @@ int ps_read_process (int pid, procstat_t *ps, char *state)
                return (-1);
        }
 
-       *state = fields[2][0];
+       *state = fields[0][0];
 
        if (*state == 'Z')
        {
@@ -949,16 +972,16 @@ int ps_read_process (int pid, procstat_t *ps, char *state)
                return (0);
        }
 
-       cpu_user_counter   = atoll (fields[13]);
-       cpu_system_counter = atoll (fields[14]);
-       vmem_size          = atoll (fields[22]);
-       vmem_rss           = atoll (fields[23]);
-       ps->vmem_minflt_counter = atol (fields[9]);
-       ps->vmem_majflt_counter = atol (fields[11]);
+       cpu_user_counter   = atoll (fields[11]);
+       cpu_system_counter = atoll (fields[12]);
+       vmem_size          = atoll (fields[20]);
+       vmem_rss           = atoll (fields[21]);
+       ps->vmem_minflt_counter = atol (fields[7]);
+       ps->vmem_majflt_counter = atol (fields[9]);
 
        {
-               unsigned long long stack_start = atoll (fields[27]);
-               unsigned long long stack_ptr   = atoll (fields[28]);
+               unsigned long long stack_start = atoll (fields[25]);
+               unsigned long long stack_ptr   = atoll (fields[26]);
 
                stack_size = (stack_start > stack_ptr)
                        ? stack_start - stack_ptr