cpupower: bench: parse.c: Fix several minor errors

Resolved several minor errors in prepare_config() and made some additional improvements.
Earlier, the risk of file stream that was not closed. Misuse of strncpy, and the use of strncmp with strlen that makes it pointless.
I also check that sscanf has been successful, otherwise continue to the next line. And minimized the use of magic numbers.

This was found using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 21 insertions, 18 deletions

diff --git a/tools/power/cpupower/bench/parse.c b/tools/power/cpupower/bench/parse.c
index 543bba14ae2c..f503fb53824e 100644
--- a/tools/power/cpupower/bench/parse.c
+++ b/tools/power/cpupower/bench/parse.c
@@ -158,14 +158,15 @@ struct config *prepare_default_config()
 int prepare_config(const char *path, struct config *config)
 {
         size_t len = 0;
-        char *opt, *val, *line = NULL;
-        FILE *configfile = fopen(path, "r");
+        char opt[16], val[32], *line = NULL;
+        FILE *configfile;
 
         if (config == NULL) {
                 fprintf(stderr, "error: config is NULL\n");
                 return 1;
         }
 
+        configfile = fopen(path, "r");
         if (configfile == NULL) {
                 perror("fopen");
                 fprintf(stderr, "error: unable to read configfile\n");
@@ -174,52 +175,54 @@ int prepare_config(const char *path, struct config *config)
         }
 
         while (getline(&line, &len, configfile) != -1) {
-                if (line[0] == '#' || line[0] == ' ')
+                if (line[0] == '#' || line[0] == ' ' || line[0] == '\n')
                         continue;
 
-                sscanf(line, "%as = %as", &opt, &val);
+                if (sscanf(line, "%14s = %30s", opt, val) < 2)
+                        continue;
 
                 dprintf("parsing: %s -> %s\n", opt, val);
 
-                if (strncmp("sleep", opt, strlen(opt)) == 0)
+                if (strcmp("sleep", opt) == 0)
                         sscanf(val, "%li", &config->sleep);
 
-                else if (strncmp("load", opt, strlen(opt)) == 0)
+                else if (strcmp("load", opt) == 0)
                         sscanf(val, "%li", &config->load);
 
-                else if (strncmp("load_step", opt, strlen(opt)) == 0)
+                else if (strcmp("load_step", opt) == 0)
                         sscanf(val, "%li", &config->load_step);
 
-                else if (strncmp("sleep_step", opt, strlen(opt)) == 0)
+                else if (strcmp("sleep_step", opt) == 0)
                         sscanf(val, "%li", &config->sleep_step);
 
-                else if (strncmp("cycles", opt, strlen(opt)) == 0)
+                else if (strcmp("cycles", opt) == 0)
                         sscanf(val, "%u", &config->cycles);
 
-                else if (strncmp("rounds", opt, strlen(opt)) == 0)
+                else if (strcmp("rounds", opt) == 0)
                         sscanf(val, "%u", &config->rounds);
 
-                else if (strncmp("verbose", opt, strlen(opt)) == 0)
+                else if (strcmp("verbose", opt) == 0)
                         sscanf(val, "%u", &config->verbose);
 
-                else if (strncmp("output", opt, strlen(opt)) == 0)
+                else if (strcmp("output", opt) == 0)
                         config->output = prepare_output(val); 
 
-                else if (strncmp("cpu", opt, strlen(opt)) == 0)
+                else if (strcmp("cpu", opt) == 0)
                         sscanf(val, "%u", &config->cpu);
 
-                else if (strncmp("governor", opt, 14) == 0)
-                        strncpy(config->governor, val, 14);
+                else if (strcmp("governor", opt) == 0) {
+                        strncpy(config->governor, val,
+                                        sizeof(config->governor));
+                        config->governor[sizeof(config->governor) - 1] = '\0';
+                }
 
-                else if (strncmp("priority", opt, strlen(opt)) == 0) {
+                else if (strcmp("priority", opt) == 0) {
                         if (string_to_prio(val) != SCHED_ERR)
                                 config->prio = string_to_prio(val);
                 }
         }
 
         free(line);
-        free(opt);
-        free(val);
 
         return 0;
 }