win32: Use an 64-bit file offset type

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>

src/common.h

@@ -25,6 +25,7 @@
 #include <string.h>
 
 #include <sys/types.h>
+#include <sys/stat.h>
 
 #ifdef GIT_WIN32
 
@@ -51,6 +52,23 @@ typedef SSIZE_T ssize_t;
 #  define R_OK 4  /* read  mode check */
 # endif
 
+#if defined(__MINGW32__)
+
+# define off_t off64_t
+# define lseek _lseeki64
+# define stat _stati64
+# define fstat _fstati64
+
+#elif defined(_MSC_VER)
+
+typedef __int64 off64_t;
+# define off_t off64_t
+# define lseek _lseeki64
+# define stat _stat64
+# define fstat _fstat64
+
+#endif
+
 #else
 
 # include <unistd.h>

src/fileops.c

@@ -69,7 +69,8 @@ off_t gitfo_size(git_file fd)
 int gitfo_read_file(gitfo_buf *obj, const char *path)
 {
 	git_file fd;
-	off_t len;
+	size_t len;
+	off_t size;
 	unsigned char *buff;
 
 	assert(obj && path && *path);
@@ -77,8 +78,13 @@ int gitfo_read_file(gitfo_buf *obj, const char *path)
 	if ((fd = gitfo_open(path, O_RDONLY)) < 0)
 		return GIT_ERROR;
 
-	if (((len = gitfo_size(fd)) < 0) 
+	if (((size = gitfo_size(fd)) < 0) || !git__is_sizet(size+1)) {
-		|| ((buff = git__malloc(len + 1)) == NULL)) {
+		gitfo_close(fd);
+		return GIT_ERROR;
+	}
+	len = (size_t) size;
+
+	if ((buff = git__malloc(len + 1)) == NULL) {
 		gitfo_close(fd);
 		return GIT_ERROR;
 	}

src/fileops.h

@@ -9,7 +9,6 @@
 #include "common.h"
 #include "map.h"
 #include "dir.h"
-#include <sys/stat.h>
 #include <fcntl.h>
 #include <time.h>
 

src/win32/map.c

@@ -77,8 +77,8 @@ int git__mmap(git_map *out, size_t len, int prot, int flags, int fd, off_t offse
 		return GIT_ERROR;
 	}
 
+	assert(sizeof(off_t) == 8);
 	off_low = (DWORD)(page_start);
-	if (sizeof(off_t) > 4)
 	off_hi = (DWORD)(page_start >> 32);
 	out->data = MapViewOfFile(out->fmh, view_prot, off_hi, off_low, len);
 	if (!out->data) {