src/common/wadres.c

   1 #include <stdint.h>
   2 #include <string.h>
   3 #include <assert.h>
   4
   5 #include "common/wadres.h"
   6 #include "common/streams.h"
   7 #include "cp866.h"
   8
   9 typedef struct Entry {
  10   long offset, size;
  11   char name[8];
  12   int f;
  13 } Entry;
  14
  15 static int n_wads;
  16 static int n_resources;
  17 static Reader *wads[MAX_WADS];
  18 static Entry resources[MAX_RESOURCES];
  19
  20 static int check_header (Reader *r) {
  21   assert(r != NULL);
  22   char ident[4];
  23   r->setpos(r, 0);
  24   stream_read(ident, 4, 1, r);
  25   return (memcmp(ident, "IWAD", 4) == 0) || (memcmp(ident, "PWAD", 4) == 0);
  26 }
  27
  28 int WADRES_addwad (Reader *r) {
  29   assert(r != NULL);
  30   if (n_wads < MAX_WADS && check_header(r)) {
  31     wads[n_wads] = r;
  32     n_wads += 1;
  33     return 1;
  34   } else {
  35     return 0;
  36   }
  37 }
  38
  39 static int WADRES_addresource (const Entry *e) {
  40   assert(e != NULL);
  41   for (int i = 0; i < n_resources; ++i) {
  42     if (cp866_strncasecmp(resources[i].name, e->name, 8) == 0) {
  43       memcpy(&resources[i], e, sizeof(Entry));
  44       return i;
  45     }
  46   }
  47   if (n_resources < MAX_RESOURCES) {
  48     memcpy(&resources[n_resources], e, sizeof(Entry));
  49     n_resources += 1;
  50     return n_resources - 1;
  51   }
  52   return -1;
  53 }
  54
  55 static int WADRES_read (Reader *r) {
  56   r->setpos(r, 4); // skip magic
  57   int32_t n = stream_read32(r);
  58   int32_t dir = stream_read32(r);
  59   r->setpos(r, dir);
  60   int ok = 1;
  61   for (int32_t i = 0; ok && i < n; ++i) {
  62     Entry e;
  63     e.offset = stream_read32(r);
  64     e.size = stream_read32(r);
  65     stream_read(e.name, 8, 1, r);
  66     ok = WADRES_addresource(&e) != -1;
  67   }
  68   return ok;
  69 }
  70
  71 int WADRES_rehash (void) {
  72   int ok = 1;
  73   for (int i = 0; i < n_wads; ++i) {
  74     if (!WADRES_read(wads[i])) {
  75       ok = 0;
  76     }
  77   }
  78   return ok;
  79 }
  80
  81 int WADRES_find (const char name[8]) {
  82   int i = n_resources - 1;
  83   while (i >= 0 && cp866_strncasecmp(name, resources[i].name, 8) != 0) {
  84     i -= 1;
  85   }
  86   return i;
  87 }
  88
  89 int WADRES_maxids (void) {
  90   return n_resources;
  91 }
  92
  93 Reader *WADRES_getbasereader (int id) {
  94   assert(id >= 0 && id < n_resources);
  95   return wads[resources[id].f];
  96 }
  97
  98 long WADRES_getoffset (int id) {
  99   assert(id >= 0 && id < n_resources);
 100   return resources[id].offset;
 101 }
 102
 103 long WADRES_getsize (int id) {
 104   assert(id >= 0 && id < n_resources);
 105   return resources[id].size;
 106 }
 107
 108 void WADRES_getname (int id, char *name) {
 109   assert(id >= 0 && id < n_resources);
 110   strncpy(name, resources[id].name, 8);
 111 }
 112
 113 void WADRES_getdata (int id, void *data) {
 114   assert(id >= 0 && id < n_resources);
 115   Reader *r = wads[resources[id].f];
 116   long pos = r->getpos(r);
 117   r->setpos(r, resources[id].offset);
 118   stream_read(data, resources[id].size, 1, r);
 119   r->setpos(r, pos);
 120 }