1 files changed, 72 insertions, 0 deletions
diff --git a/src/map/grfio.cpp b/src/map/grfio.cpp
new file mode 100644
index 0000000..a190d1b
--- /dev/null
+++ b/src/map/grfio.cpp
@@ -0,0 +1,72 @@
+// Reads .gat files by name-mapping .wlk files
+#include "grfio.hpp"
+
+#include <sys/stat.h>
+
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <cassert>
+#include <cstdio>
+#include <cstring>
+
+#include <fstream>
+#include <map>
+
+#include "../common/cxxstdio.hpp"
+#include "../common/extract.hpp"
+
+#include "../poison.hpp"
+
+static
+std::map<std::string, std::string> load_resnametable()
+{
+    std::ifstream in("data/resnametable.txt");
+    if (!in.is_open())
+    {
+        fprintf(stderr, "Missing data/resnametable.txt");
+        abort();
+    }
+    std::map<std::string, std::string> out;
+
+    std::string line;
+    while (std::getline(in, line))
+    {
+        std::string key, value;
+        if (!extract(line,
+                    record<'#'>(&key, &value)))
+            continue;
+        out[key] = value;
+    }
+    return out;
+}
+
+/// Change *.gat to *.wlk
+static
+std::string grfio_resnametable(const_string rname)
+{
+    static
+    std::map<std::string, std::string> resnametable = load_resnametable();
+
+    return resnametable.at(std::string(rname.begin(), rname.end()));
+}
+
+std::vector<uint8_t> grfio_reads(const_string rname)
+{
+    std::string lfname = "data/" + grfio_resnametable(rname);
+
+    int fd = open(lfname.c_str(), O_RDONLY);
+    if (fd == -1)
+    {
+        FPRINTF(stderr, "Resource %s (file %s) not found\n",
+                std::string(rname.begin(), rname.end()), lfname);
+        return {};
+    }
+    off_t len = lseek(fd, 0, SEEK_END);
+    assert (len != -1);
+    std::vector<uint8_t> buffer(len);
+    int err = pread(fd, buffer.data(), len, 0);
+    assert (err == len);
+    close(fd);
+    return buffer;
+}