libupkg.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3
   4 #include "upkg.h"
   5 #include "pack.h"
   6
   7
   8 struct upkg_private {
   9         FILE *f;
  10
  11
  12         unsigned long name_offset, export_offset, import_offset;
  13         unsigned char guid[16];
  14 };
  15
  16 static struct upkg *init_upkg(unsigned char hdr[static UPKG_HDR_SIZE])
  17 {
  18         struct upkg *pkg;
  19
  20         pkg = malloc(sizeof *pkg);
  21         if (!pkg) {
  22                 return NULL;
  23         }
  24
  25         pkg->priv = malloc(sizeof *pkg->priv);
  26         if (!pkg->priv) {
  27                 free(pkg);
  28                 return NULL;
  29         }
  30
  31         pkg->version      = unpack_16_le(hdr+4);
  32         pkg->license      = unpack_16_le(hdr+6);
  33         pkg->flags        = unpack_32_le(hdr+8);
  34         pkg->name_count   = unpack_32_le(hdr+12);
  35         pkg->export_count = unpack_32_le(hdr+20);
  36         pkg->import_count = unpack_32_le(hdr+28);
  37
  38         pkg->priv->name_offset   = unpack_32_le(hdr+16);
  39         pkg->priv->export_offset = unpack_32_le(hdr+24);
  40         pkg->priv->import_offset = unpack_32_le(hdr+32);
  41
  42         return pkg;
  43 }
  44
  45 struct upkg *upkg_fopen(const char *path)
  46 {
  47         unsigned char hdr_buf[UPKG_HDR_SIZE];
  48         struct upkg *pkg;
  49         FILE *f;
  50
  51         if (!(f = fopen(path, "rb"))) {
  52                 return NULL;
  53         }
  54         if (fread(hdr_buf, sizeof hdr_buf, 1, f) != 1) {
  55                 goto err;
  56         }
  57         if (unpack_32_le(hdr_buf) != UPKG_HDR_MAGIC) {
  58                 goto err;
  59         }
  60
  61         /* Initialize package structure. */
  62         pkg = init_upkg(hdr_buf);
  63         if (!pkg) {
  64                 goto err;
  65         }
  66         pkg->priv->f = f;
  67
  68         return pkg;
  69 err:
  70         fclose(f);
  71         return NULL;
  72 }
  73
  74 int upkg_close(struct upkg *pkg)
  75 {
  76         if (pkg->priv->f)
  77                 return fclose(pkg->priv->f);
  78         return 0;
  79 }