C/Read an ini file

Revision as of 16:45, 17 October 2011

1. include <stdio.h>
2. include <stdlib.h>
3. include <string.h>

1. define CHUNK_SIZE 128

enum lineTypes {

 unknown,
 empty,
 comment,
 sectionHead,
 variableOnly,
 variableValue

};

struct lineByLine {

 char *line;
 int length;
 enum lineTypes type;

};

int main(int argc, char *argv[]) {

 FILE *f;
 void *p;
 
 struct lineByLine *lines;
 struct lineByLine *tline;
 int linec;
 
 int isNewline;
 char *c; /* contents*/
 int i;
 int l; /* length */
 int r; /* amount read */
 int s; /* memory size */

 f = fopen("php.ini","r");
 if (!f) {
   perror("fopen()");
   exit(1);
 }

 c = NULL;
 l = 0;
 s = 0;
 while (!feof(f)) {
   s += CHUNK_SIZE;
   p = realloc(c, sizeof(char) * s);
   if (!p) {
     perror("realloc()");
     goto die1;
   }
   c = p;
   r = fread(&(c[l]), 1, s - l, f);
   if (!r) {
     fprintf(stderr,"EOF?\n");
     break;
   } else if (r < 0) {
     perror("fread()");
     break;
   }
   l += r;
 }
 
 p = realloc(c, sizeof(char) * (l + 1));
 if (!p) {
   perror("realloc()");
 } else {
   c = p;
 }
 
 c[l] = '\0';
 
 lines = NULL;
 linec = 0;
 isNewline = 1;
 for (i = 0; i <= l; i++) {
   if (isNewline) {
     isNewline = 0;
     p = realloc(lines, sizeof(struct lineByLine) * (linec + 1));
     if (!p) {
       perror("realloc()");
       goto die2;
     }
     lines = p;
     tline = &(lines[linec]);
     tline->line = &(c[i]);
     tline->length = -1;
     tline->type = unknown;
     linec++;
   }
   if (i == l || c[i] == '\n') {
     isNewline = 1;
     if (i < l) c[i] = '\0';
     if (linec > 0) {
       tline = &(lines[linec-1]);
       tline->length = strlen(tline->line);
       switch (tline->line[0]) {
         case '\0': tline->type = empty; break;
         case ';':  tline->type = comment; break;
         case '[':  tline->type = sectionHead; break;
         default:
           if (strchr(tline->line,'=')) {
             tline->type = variableValue;
           } else {
             tline->type = variableOnly;
           }
       }
     }
   }
 }
 
 for (i = 0; i < linec; i++) {
   tline = &(lines[i]);
   printf("%6d-%d-%3d:  %s\n",
           i,
           tline->type,
           tline->length,
           tline->line);
 }
 
 return 0;

die2:

 if (lines) free(lines);

die1:

 if (c) free(c);

die:

 return 1;

}