txt.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include <unistd.h>
   4 #include "ctxt.h"
   5 #include "util.h"
   6
   7 static char *file_read(int fd)
   8 {
   9         int size = 1024;
  10         char *buf = xmalloc(size);
  11         int n = 0;
  12         int c = 0;
  13         while ((c = read(fd, buf + n, size - n)) > 0) {
  14                 n += c;
  15                 if (n == size) {
  16                         char *newbuf = xmalloc(size * 2);
  17                         memcpy(newbuf, buf, n);
  18                         free(buf);
  19                         buf = newbuf;
  20                         size *= 2;
  21                 }
  22         }
  23         return buf;
  24 }
  25
  26 static int newlines(char *s)
  27 {
  28         int i;
  29         for (i = 0; (s = strchr(s, '\n')); i++, s++);
  30         return i;
  31 }
  32
  33 static void initlines(struct txt *txt)
  34 {
  35         int i;
  36         txt->lines[0] = txt->txt;
  37         for (i = 1; i <= txt->n; i++) {
  38                 char *s = strchr(txt->lines[i - 1], '\n');
  39                 if (s)
  40                         *s = '\0';
  41                 if (i < txt->n)
  42                         txt->lines[i] = s + 1;
  43         }
  44 }
  45
  46 struct txt *txt_alloc(int fd)
  47 {
  48         struct txt *txt = xmalloc(sizeof(struct txt));
  49         txt->txt = file_read(fd);
  50         txt->n = newlines(txt->txt);
  51         txt->lines = xmalloc(sizeof(*txt->lines) * txt->n);
  52         initlines(txt);
  53         return txt;
  54 }
  55
  56 char *txt_line(struct txt *txt, int line)
  57 {
  58         if (line < txt->n)
  59                 return txt->lines[line];
  60         return NULL;
  61 }
  62
  63 void txt_free(struct txt *txt)
  64 {
  65         free(txt->lines);
  66         free(txt->txt);
  67 }