Load config files faster (#3505)

Also fixed issue with parameter_is_number that didn't parse negative numbers properly

src/bflib_basics.c

@@ -595,6 +595,19 @@ void make_uppercase(char * string) {
   }
 }
 
+int natoi(const char * str, int len) {
+  int value = -1;
+  for (int i = 0; i < len; ++i) {
+    if (!isdigit(str[i])) {
+      return value;
+    } else if (value < 0) {
+      value = 0;
+    }
+    value = (value * 10) + (str[i] - '0');
+  }
+  return value;
+}
+
 /******************************************************************************/
 #ifdef __cplusplus
 }

src/bflib_basics.h

@@ -182,6 +182,7 @@ long saturate_set_signed(long long val,unsigned short nbits);
 unsigned long saturate_set_unsigned(unsigned long long val,unsigned short nbits);
 void make_lowercase(char *);
 void make_uppercase(char *);
+int natoi(const char * str, int len); // like atoi but stops after len bytes
 
 /**
  * Converts an index number to a flag - by creating a bitmask where only the nth bit is set to 1.

src/config.c

@@ -375,6 +375,81 @@ short find_conf_block(const char *buf,long *pos,long buflen,const char *blocknam
   return -1;
 }
 
+/**
+ * Reads the block name from buf, starting at pos.
+ * Sets name and namelen to the block name and name length respectively.
+ * Returns true on success, false when the block name is zero.
+ */
+TbBool conf_get_block_name(const char * buf, long * pos, long buflen, const char ** name, int * namelen)
+{
+  const long start = *pos;
+  *name = NULL;
+  *namelen = 0;
+  while (true) {
+    if (*pos >= buflen) {
+      return false;
+    } else if (isalpha(buf[*pos])) {
+      (*pos)++;
+      continue;
+    } else if (isdigit(buf[*pos])) {
+      (*pos)++;
+      continue;
+    } else {
+      if (*pos - start > 0) {
+        *name = &buf[start];
+        *namelen = *pos - start;
+        return true;
+      } else {
+        return false;
+      }
+    }
+  }
+}
+
+/**
+ * Searches for the next block in buf, starting at pos.
+ * Sets name and namelen to the block name and name length respectively.
+ * Returns true on success, false when no more blocks are found.
+ */
+TbBool iterate_conf_blocks(const char * buf, long * pos, long buflen, const char ** name, int * namelen)
+{
+  text_line_number = 1;
+  *name = NULL;
+  *namelen = 0;
+  while (true) {
+    // Skip whitespace before block start
+    if (!skip_conf_spaces(buf, pos, buflen)) {
+      return false;
+    }
+    // Check if this line is start of a block
+    if (*pos >= buflen) {
+      return false;
+    } else if (buf[*pos] != '[') {
+      skip_conf_to_next_line(buf, pos, buflen);
+      continue;
+    }
+    (*pos)++;
+    // Skip whitespace before block name
+    if (!skip_conf_spaces(buf, pos, buflen)) {
+      return false;
+    }
+    // Get block name
+    if (!conf_get_block_name(buf, pos, buflen, name, namelen)) {
+      skip_conf_to_next_line(buf, pos, buflen);
+      return false;
+    }
+    // Skip whitespace after block name
+    if (!skip_conf_spaces(buf, pos, buflen)) {
+      return false;
+    } else if (buf[*pos] != ']') {
+      skip_conf_to_next_line(buf, pos, buflen);
+      continue;
+    }
+    skip_conf_to_next_line(buf,pos,buflen);
+    return true;
+  }
+}
+
 /**
  * Recognizes config command and returns its number, or negative status code.
  * @param buf

src/config.h

@@ -327,6 +327,7 @@ TbBool reset_credits(struct CreditsItem *credits);
 TbBool setup_campaign_credits_data(struct GameCampaign *campgn);
 /******************************************************************************/
 short find_conf_block(const char *buf,long *pos,long buflen,const char *blockname);
+TbBool iterate_conf_blocks(const char * buf, long * pos, long buflen, const char ** name, int * namelen);
 int recognize_conf_command(const char *buf,long *pos,long buflen,const struct NamedCommand *commands);
 TbBool skip_conf_to_next_line(const char *buf,long *pos,long buflen);
 int get_conf_parameter_single(const char *buf,long *pos,long buflen,char *dst,long dstlen);