configfile.c

   1 /* configfile.c: parsing of config files
   2  *
   3  * Copyright (C) 2008 Lars Hjemli
   4  *
   5  * Licensed under GNU General Public License v2
   6  *   (see COPYING for full license text)
   7  */
   8
   9 #include <ctype.h>
  10 #include <stdio.h>
  11 #include "configfile.h"
  12
  13 static int next_char(FILE *f)
  14 {
  15         int c = fgetc(f);
  16         if (c == '\r') {
  17                 c = fgetc(f);
  18                 if (c != '\n') {
  19                         ungetc(c, f);
  20                         c = '\r';
  21                 }
  22         }
  23         return c;
  24 }
  25
  26 static void skip_line(FILE *f)
  27 {
  28         int c;
  29
  30         while ((c = next_char(f)) && c != '\n' && c != EOF)
  31                 ;
  32 }
  33
  34 static int read_config_line(FILE *f, struct strbuf *name, struct strbuf *value)
  35 {
  36         int c = next_char(f);
  37
  38         strbuf_reset(name);
  39         strbuf_reset(value);
  40
  41         /* Skip comments and preceding spaces. */
  42         for(;;) {
  43                 if (c == '#' || c == ';')
  44                         skip_line(f);
  45                 else if (!isspace(c))
  46                         break;
  47                 c = next_char(f);
  48         }
  49
  50         /* Read variable name. */
  51         while (c != '=') {
  52                 if (c == '\n' || c == EOF)
  53                         return 0;
  54                 strbuf_addch(name, c);
  55                 c = next_char(f);
  56         }
  57
  58         /* Read variable value. */
  59         c = next_char(f);
  60         while (c != '\n' && c != EOF) {
  61                 strbuf_addch(value, c);
  62                 c = next_char(f);
  63         }
  64
  65         return 1;
  66 }
  67
  68 int parse_configfile(const char *filename, configfile_value_fn fn)
  69 {
  70         static int nesting;
  71         struct strbuf name = STRBUF_INIT;
  72         struct strbuf value = STRBUF_INIT;
  73         FILE *f;
  74
  75         /* cancel deeply nested include-commands */
  76         if (nesting > 8)
  77                 return -1;
  78         if (!(f = fopen(filename, "r")))
  79                 return -1;
  80         nesting++;
  81         while (read_config_line(f, &name, &value))
  82                 fn(name.buf, value.buf);
  83         nesting--;
  84         fclose(f);
  85         strbuf_release(&name);
  86         strbuf_release(&value);
  87         return 0;
  88 }
  89