Add config file API.

config_file.c

@@ -0,0 +1,271 @@
+#include "config_file.h"
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <ctype.h>
+
+struct entry_list
+{
+   char *key;
+   char *value;
+   struct entry_list *next;
+};
+
+struct config_file
+{
+   struct entry_list *entries;
+};
+
+static char *getaline(FILE *file)
+{
+   char *newline = malloc(8);
+   size_t cur_size = 8;
+   size_t index = 0;
+
+   int in = getc(file);
+   while (in != EOF && in != '\n')
+   {
+      if (index == cur_size)
+      {
+         cur_size *= 2;
+         newline = realloc(newline, cur_size);
+      }
+
+      newline[index++] = in;
+      in = getc(file);
+   }
+   return newline; 
+}
+
+static bool parse_line(struct entry_list *list, char *line)
+{
+   // Remove everything after comment.
+   char *comment = strchr(line, '#');
+   if (comment)
+      *comment = '\0';
+
+   // Skips to first character.
+   while (isspace(*line))
+      line++;
+
+   char *key = malloc(8);
+   size_t cur_size = 8;
+   size_t index = 0;
+
+   while (isgraph(*line))
+   {
+      if (index == cur_size)
+      {
+         cur_size *= 2;
+         key = realloc(key, cur_size);
+      }
+
+      key[index++] = *line++;
+   }
+   list->key = key;
+
+   while (isspace(*line))
+      line++;
+
+   // If we don't have an equal sign here, we've got an invalid string...
+   if (*line != '=')
+   {
+      list->key = NULL;
+      free(key);
+      return false;
+   }
+   line++;
+
+   while (isspace(*line))
+      line++;
+
+   // We have a full string. Read until next ".
+   if (*line == '"')
+   {
+      char *tok = strtok(line + 1, "\"");
+      if (tok == NULL)
+      {
+         list->key = NULL;
+         free(key);
+         return false;
+      }
+      list->value = strdup(tok);
+   }
+   else // We don't have that... Read till next space.
+   {
+      char *tok = strtok(line, " \t\f");
+      if (tok == NULL)
+      {
+         list->key = NULL;
+         free(key);
+         return false;
+      }
+      list->value = strdup(tok);
+   }
+
+   return true;
+}
+
+static void print_config(config_file_t *conf)
+{
+   struct entry_list *tmp = conf->entries;
+   while (tmp != NULL)
+   {
+      printf("Key: \"%s\", Value: \"%s\"\n", tmp->key, tmp->value);
+      tmp = tmp->next;
+   }
+}
+
+config_file_t *config_file_new(const char *path)
+{
+   FILE *file = fopen(path, "r");
+   if (!file)
+      return NULL;
+
+   struct config_file *conf = calloc(1, sizeof(*conf));
+   if (conf == NULL)
+      return NULL;
+
+   struct entry_list *tail = conf->entries;
+
+   while (!feof(file))
+   {
+      struct entry_list *list = calloc(1, sizeof(*list));
+      char *line = getaline(file);
+
+      if (line)
+      {
+         if (parse_line(list, line))
+         {
+            if (conf->entries == NULL)
+            {
+               conf->entries = list;
+               tail = list;
+            }
+            else
+            {
+               tail->next = list;
+               tail = list;
+            }
+         }
+         free(line);
+      }
+   }
+   fclose(file);
+
+   //print_config(conf);
+
+   return conf;
+}
+
+void config_file_free(config_file_t *conf)
+{
+   if (conf != NULL)
+   {
+      struct entry_list *tmp = conf->entries;
+      struct entry_list *old = tmp;
+      while (tmp != NULL)
+      {
+         free(tmp->key);
+         free(tmp->value);
+         old = tmp;
+         tmp = tmp->next;
+         free(old);
+      }
+      free(conf);
+   }
+}
+
+bool config_get_double(config_file_t *conf, const char *key, double *in)
+{
+   struct entry_list *list = conf->entries;
+
+   while (list != NULL)
+   {
+      if (strcmp(key, list->key) == 0)
+      {
+         *in = strtod(list->value, NULL);
+         return true;
+      }
+      list = list->next;
+   }
+   return false;
+}
+
+bool config_get_int(config_file_t *conf, const char *key, int *in)
+{
+   struct entry_list *list = conf->entries;
+
+   while (list != NULL)
+   {
+      if (strcmp(key, list->key) == 0)
+      {
+         *in = strtol(list->value, NULL, 0);
+         return true;
+      }
+      list = list->next;
+   }
+   return false;
+}
+
+bool config_get_char(config_file_t *conf, const char *key, char *in)
+{
+   struct entry_list *list = conf->entries;
+
+   while (list != NULL)
+   {
+      if (strcmp(key, list->key) == 0)
+      {
+         if (strlen(list->value) > 1)
+            return false;
+         *in = *list->value;
+         return true;
+      }
+      list = list->next;
+   }
+   return false;
+}
+
+bool config_get_string(config_file_t *conf, const char *key, char **str)
+{
+   struct entry_list *list = conf->entries;
+
+   while (list != NULL)
+   {
+      if (strcmp(key, list->key) == 0)
+      {
+         *str = strdup(list->value);
+         return true;
+      }
+      list = list->next;
+   }
+   return false;
+}
+
+bool config_get_bool(config_file_t *conf, const char *key, bool *in)
+{
+   struct entry_list *list = conf->entries;
+
+   while (list != NULL)
+   {
+      if (strcmp(key, list->key) == 0)
+      {
+         if (strcasecmp(list->value, "true") == 0)
+            *in = true;
+         else if (strcasecmp(list->value, "1") == 0)
+            *in = true;
+         else if (strcasecmp(list->value, "false") == 0)
+            *in = false;
+         else if (strcasecmp(list->value, "0") == 0)
+            *in = false;
+         else
+            return false;
+
+         return true;
+      }
+      list = list->next;
+   }
+   return false;
+}
+
+

config_file.h

@@ -0,0 +1,20 @@
+#ifndef __CONFIG_FILE_H
+#define __CONFIG_FILE_H
+
+#include <stdint.h>
+#include <stdbool.h>
+
+typedef struct config_file config_file_t;
+
+config_file_t *config_file_new(const char *path);
+void config_file_free(config_file_t *conf);
+
+bool config_get_double(config_file_t *conf, const char *entry, double *in);
+bool config_get_int(config_file_t *conf, const char *entry, int *in);
+bool config_get_char(config_file_t *conf, const char *entry, char *in);
+bool config_get_string(config_file_t *conf, const char *entry, char **in);
+bool config_get_bool(config_file_t *conf, const char *entry, bool *in);
+
+
+
+#endif