Util: VFile using FILE* backing

src/util/vfs.h

@@ -53,8 +53,10 @@ struct VDir {
 };
 
 struct VFile* VFileOpen(const char* path, int flags);
+struct VFile* VFileFOpen(const char* path, const char* mode);
 struct VFile* VFileFromFD(int fd);
 struct VFile* VFileFromMemory(void* mem, size_t size);
+struct VFile* VFileFromFILE(FILE* file);
 
 struct VDir* VDirOpen(const char* path);
 

src/util/vfs/vfs-file.c

@@ -0,0 +1,132 @@
+/* Copyright (c) 2013-2015 Jeffrey Pfau
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#include "util/vfs.h"
+
+#include "util/memory.h"
+
+#include <stdio.h>
+
+struct VFileFILE {
+	struct VFile d;
+	FILE* file;
+};
+
+static bool _vffClose(struct VFile* vf);
+static off_t _vffSeek(struct VFile* vf, off_t offset, int whence);
+static ssize_t _vffRead(struct VFile* vf, void* buffer, size_t size);
+static ssize_t _vffWrite(struct VFile* vf, const void* buffer, size_t size);
+static void* _vffMap(struct VFile* vf, size_t size, int flags);
+static void _vffUnmap(struct VFile* vf, void* memory, size_t size);
+static void _vffTruncate(struct VFile* vf, size_t size);
+static ssize_t _vffSize(struct VFile* vf);
+
+struct VFile* VFileFOpen(const char* path, const char* mode) {
+	if (!path && !mode) {
+		return 0;
+	}
+	FILE* file = fopen(path, mode);
+	return VFileFromFILE(file);
+}
+
+struct VFile* VFileFromFILE(FILE* file) {
+	if (!file) {
+		return 0;
+	}
+
+	struct VFileFILE* vff = malloc(sizeof(struct VFileFILE));
+	if (!vff) {
+		return 0;
+	}
+
+	vff->file = file;
+	vff->d.close = _vffClose;
+	vff->d.seek = _vffSeek;
+	vff->d.read = _vffRead;
+	vff->d.readline = VFileReadline;
+	vff->d.write = _vffWrite;
+	vff->d.map = _vffMap;
+	vff->d.unmap = _vffUnmap;
+	vff->d.truncate = _vffTruncate;
+	vff->d.size = _vffSize;
+
+	return &vff->d;
+}
+
+bool _vffClose(struct VFile* vf) {
+	struct VFileFILE* vff = (struct VFileFILE*) vf;
+	if (fclose(vff->file) < 0) {
+		return false;
+	}
+	free(vff);
+	return true;
+}
+
+off_t _vffSeek(struct VFile* vf, off_t offset, int whence) {
+	struct VFileFILE* vff = (struct VFileFILE*) vf;
+	return fseek(vff->file, offset, whence);
+}
+
+ssize_t _vffRead(struct VFile* vf, void* buffer, size_t size) {
+	struct VFileFILE* vff = (struct VFileFILE*) vf;
+	return fread(buffer, size, 1, vff->file);
+}
+
+ssize_t _vffWrite(struct VFile* vf, const void* buffer, size_t size) {
+	struct VFileFILE* vff = (struct VFileFILE*) vf;
+	return fwrite(buffer, size, 1, vff->file);
+}
+
+static void* _vffMap(struct VFile* vf, size_t size, int flags) {
+	UNUSED(flags);
+	struct VFileFILE* vff = (struct VFileFILE*) vf;
+	void* mem = anonymousMemoryMap(size);
+	if (!mem) {
+		return 0;
+	}
+	long pos = ftell(vff->file);
+	fseek(vff->file, 0, SEEK_SET);
+	fread(mem, size, 1, vff->file);
+	fseek(vff->file, pos, SEEK_SET);
+	return mem;
+}
+
+static void _vffUnmap(struct VFile* vf, void* memory, size_t size) {
+	struct VFileFILE* vff = (struct VFileFILE*) vf;
+	long pos = ftell(vff->file);
+	fseek(vff->file, 0, SEEK_SET);
+	fwrite(memory, size, 1, vff->file);
+	fseek(vff->file, pos, SEEK_SET);
+	mappedMemoryFree(memory, size);
+}
+
+static void _vffTruncate(struct VFile* vf, size_t size) {
+	struct VFileFILE* vff = (struct VFileFILE*) vf;
+	long pos = ftell(vff->file);
+	fseek(vff->file, 0, SEEK_END);
+	ssize_t realSize = ftell(vff->file);
+	if (realSize < 0) {
+		return;
+	}
+	while (size > (size_t) realSize) {
+		static const char zeros[128] = "";
+		size_t diff = size - realSize;
+		if (diff > sizeof(zeros)) {
+			diff = sizeof(zeros);
+		}
+		fwrite(zeros, diff, 1, vff->file);
+		realSize += diff;
+	}
+	fseek(vff->file, pos, SEEK_SET);
+}
+
+static ssize_t _vffSize(struct VFile* vf) {
+	struct VFileFILE* vff = (struct VFileFILE*) vf;
+	long pos = ftell(vff->file);
+	fseek(vff->file, 0, SEEK_END);
+	ssize_t size = ftell(vff->file);
+	fseek(vff->file, pos, SEEK_SET);
+	return size;
+}