]> wimlib.net Git - wimlib/blobdiff - examples/decompressfile.c
examples: C++ and Windows compatibility
[wimlib] / examples / decompressfile.c
index cc2b758e5d49644fda3b21f00fff73125993c0dd..e5a03b44512b4bd5e7a3223fb64d25237f0ff8dc 100644 (file)
@@ -3,7 +3,7 @@
  *
  * The following copying information applies to this specific source code file:
  *
- * Written in 2014 by Eric Biggers <ebiggers3@gmail.com>
+ * Written in 2014-2016 by Eric Biggers <ebiggers3@gmail.com>
  *
  * To the extent possible under law, the author(s) have dedicated all copyright
  * and related and neighboring rights to this software to the public domain
  * chunks.  A real format would need to have checksums and other metadata.
  */
 
-#define _GNU_SOURCE
 #define _FILE_OFFSET_BITS 64
 
+#if defined(_MSC_VER) && _MSC_VER < 1800 /* VS pre-2013? */
+#  define PRIu64 "I64u"
+#  define PRIu32 "u"
+#else
+#  define __STDC_FORMAT_MACROS 1
+#  include <inttypes.h>
+#endif
+
 #include <wimlib.h>
 
 #include <errno.h>
-#include <error.h>
 #include <fcntl.h>
-#include <inttypes.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
+#ifdef _WIN32
+#  include <io.h>
+#else
+#  include <unistd.h>
+#endif
+
+/*
+ * Windows compatibility defines for string encoding.  Applications using wimlib
+ * that need to run on both UNIX and Windows will need to do something similar
+ * to this, whereas applications that only need to run on one or the other can
+ * just use their platform's convention directly.
+ */
+#ifdef _WIN32
+#  define main         wmain
+   typedef wchar_t     tchar;
+#  define TS           "ls"
+#  define topen                _wopen
+#else
+   typedef char                tchar;
+#  define TS           "s"
+#  define topen                open
+#  define O_BINARY     0
+#endif
 
 static void
-do_decompress(int in_fd, const char *in_filename,
-             int out_fd, const char *out_filename,
+fatal_error(int err, const char *format, ...)
+{
+       va_list va;
+
+       va_start(va, format);
+       vfprintf(stderr, format, va);
+       if (err != 0)
+               fprintf(stderr, ": %s\n", strerror(err));
+       else
+               fputc('\n', stderr);
+       va_end(va);
+       exit(1);
+}
+
+static void
+do_decompress(int in_fd, const tchar *in_filename,
+             int out_fd, const tchar *out_filename,
              uint32_t chunk_size, struct wimlib_decompressor *decompressor)
 {
        uint64_t chunk_num;
 
-       char *ubuf = malloc(chunk_size);
-       char *cbuf = malloc(chunk_size - 1);
+       char *ubuf = (char *)malloc(chunk_size);
+       char *cbuf = (char *)malloc(chunk_size - 1);
 
        for (chunk_num = 1; ; chunk_num++) {
-               ssize_t bytes_read;
+               int32_t bytes_read;
                uint32_t usize;
                uint32_t csize;
 
@@ -80,56 +123,61 @@ do_decompress(int in_fd, const char *in_filename,
                if (bytes_read != sizeof(uint32_t) ||
                    read(in_fd, &csize, sizeof(uint32_t)) != sizeof(uint32_t))
                {
-                       error(1, errno, "Error reading \"%s\"", in_filename);
+                       fatal_error(errno, "Error reading \"%" TS"\"",
+                                   in_filename);
                }
 
                if (csize > usize || usize > chunk_size)
-                       error(1, 0, "The data is invalid!");
+                       fatal_error(0, "The data is invalid!");
 
                if (usize == csize) {
-                       if (read(in_fd, ubuf, usize) != usize) {
-                               error(1, errno, "Error reading \"%s\"",
-                                     in_filename);
+                       if (read(in_fd, ubuf, usize) != (int32_t)usize) {
+                               fatal_error(errno, "Error reading \"%" TS"\"",
+                                           in_filename);
                        }
                } else {
-                       if (read(in_fd, cbuf, csize) != csize) {
-                               error(1, errno, "Error reading \"%s\"",
-                                     in_filename);
+                       if (read(in_fd, cbuf, csize) != (int32_t)csize) {
+                               fatal_error(errno, "Error reading \"%" TS"\"",
+                                           in_filename);
                        }
 
                        if (wimlib_decompress(cbuf, csize, ubuf, usize,
                                              decompressor))
                        {
-                               error(1, 0, "The compressed data is invalid!");
+                               fatal_error(0,
+                                           "The compressed data is invalid!");
                        }
                }
 
-               printf("Chunk %"PRIu64": %"PRIu32" => %"PRIu32" bytes\n",
+               printf("Chunk %" PRIu64": %" PRIu32" => %" PRIu32" bytes\n",
                       chunk_num, csize, usize);
 
                /* Output the uncompressed chunk size, the compressed chunk
                 * size, then the chunk data.  Note: a real program would need
                 * to output the chunk sizes in consistent endianness.  */
-               if (write(out_fd, ubuf, usize) != usize)
-                       error(1, errno, "Error writing to \"%s\"", out_filename);
+               if (write(out_fd, ubuf, usize) != (int32_t)usize) {
+                       fatal_error(errno, "Error writing to \"%" TS"\"",
+                                   out_filename);
+               }
        }
        free(ubuf);
        free(cbuf);
 }
 
-int main(int argc, char **argv)
+int main(int argc, tchar **argv)
 {
-       const char *in_filename;
-       const char *out_filename;
+       const tchar *in_filename;
+       const tchar *out_filename;
        int in_fd;
        int out_fd;
-       uint32_t ctype;
+       uint32_t ctype32;
+       enum wimlib_compression_type ctype;
        uint32_t chunk_size;
        int ret;
        struct wimlib_decompressor *decompressor;
 
        if (argc != 3) {
-               fprintf(stderr, "Usage: %s INFILE OUTFILE\n", argv[0]);
+               fprintf(stderr, "Usage: %" TS" INFILE OUTFILE\n", argv[0]);
                return 2;
        }
 
@@ -137,24 +185,26 @@ int main(int argc, char **argv)
        out_filename = argv[2];
 
        /* Open input file and output file.  */
-       in_fd = open(in_filename, O_RDONLY);
+       in_fd = topen(in_filename, O_RDONLY | O_BINARY);
        if (in_fd < 0)
-               error(1, errno, "Failed to open \"%s\"", in_filename);
-       out_fd = open(out_filename, O_WRONLY | O_TRUNC | O_CREAT, 0644);
+               fatal_error(errno, "Failed to open \"%" TS"\"", in_filename);
+       out_fd = topen(out_filename, O_WRONLY | O_TRUNC | O_CREAT | O_BINARY,
+                      0644);
        if (out_fd < 0)
-               error(1, errno, "Failed to open \"%s\"", out_filename);
+               fatal_error(errno, "Failed to open \"%" TS"\"", out_filename);
 
        /* Get compression type and chunk size.  */
-       if (read(in_fd, &ctype, sizeof(uint32_t)) != sizeof(uint32_t) ||
+       if (read(in_fd, &ctype32, sizeof(uint32_t)) != sizeof(uint32_t) ||
            read(in_fd, &chunk_size, sizeof(uint32_t)) != sizeof(uint32_t))
-               error(1, errno, "Error reading from \"%s\"", in_filename);
+               fatal_error(errno, "Error reading from \"%" TS"\"", in_filename);
+       ctype = (enum wimlib_compression_type)ctype32;
 
        /* Create a decompressor for the compression type and chunk size with
         * the default parameters.  */
        ret = wimlib_create_decompressor(ctype, chunk_size, &decompressor);
        if (ret != 0)
-               error(1, 0, "Failed to create decompressor: %s",
-                     wimlib_get_error_string(ret));
+               fatal_error(0, "Failed to create decompressor: %" TS,
+                           wimlib_get_error_string((enum wimlib_error_code)ret));
 
        /* Decompress and write the data.  */
        do_decompress(in_fd, in_filename,
@@ -163,7 +213,7 @@ int main(int argc, char **argv)
 
        /* Cleanup and return.  */
        if (close(out_fd))
-               error(1, errno, "Error closing \"%s\"", out_filename);
+               fatal_error(errno, "Error closing \"%" TS"\"", out_filename);
        wimlib_free_decompressor(decompressor);
        return 0;
 }