txt.c

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