skip file format

include/file.h

@@ -2,6 +2,7 @@
 #define GUARD_5B2A3676BBB85E5075C01FF213126C89
 
 #include "types.h"
+#include <stdio.h>
 
 struct sw_filebuffer {
 	u8 *_data;
@@ -9,6 +10,7 @@ struct sw_filebuffer {
 	u32 size;
 };
 
+/* TODO: use skunkworks overlay paths */
 u8 *sw_file_load(char *path, u32 *out_size);
 
 struct sw_filebuffer *sw_filebuffer_create(u32 size);
@@ -17,4 +19,24 @@ void sw_filebuffer_destroy(struct sw_filebuffer *buf);
 
 void sw_filebuffer_read(struct sw_filebuffer *buf, void *dst, u32 count);
 
+/* fwrite helpers */
+
+void sw_fwrite_u8(FILE *fil, u8 val);
+void sw_fwrite_i8(FILE *fil, i8 val);
+void sw_fwrite_u16(FILE *fil, u16 val);
+void sw_fwrite_i16(FILE *fil, u16 val);
+void sw_fwrite_u32(FILE *fil, u32 val);
+void sw_fwrite_i32(FILE *fil, u32 val);
+void sw_fwrite_u64(FILE *fil, u64 val);
+void sw_fwrite_i64(FILE *fil, u64 val);
+void sw_fwrite_f32(FILE *fil, f32 val);
+void sw_fwrite_f64(FILE *fil, f64 val);
+void sw_fwrite_bool(FILE *fil, bool val);
+
+void sw_fwrite_str_nozero(FILE *fil, char *str);
+void sw_fwrite_str_zero(FILE *fil, char *str);
+void sw_fwrite_str_prefix8(FILE *fil, char *str);
+void sw_fwrite_str_prefix16(FILE *fil, char *str);
+void sw_fwrite_str_prefix32(FILE *fil, char *str);
+
 #endif /* GUARD_5B2A3676BBB85E5075C01FF213126C89 */

include/skip.h

@@ -0,0 +1,57 @@
+/******************************************************************************/
+/* Skip File Format, skunkworks zip                                           */
+/*                                                                            */
+/* little-endian                                                              */
+/*                                                                            */
+/* Main Header:                                                               */
+/*                                                                            */
+/* bytes | what                                                               */
+/* ------+------------------------------------------------------------------- */
+/*     4 | 'SWZP'                                                             */
+/*     1 | version, currently 0x00                                            */
+/*     1 | compression format, currently only 0 supported, uncompressed       */
+/*     4 | size of uncompressed data chunk                                    */
+/*     4 | size of compressed data chunk (same as compressed if format 0)     */
+/*     2 | file count                                                         */
+/*                                                                            */
+/* File Header (appears 'file count' times in a row):                         */
+/*                                                                            */
+/* bytes | what                                                               */
+/* ------+------------------------------------------------------------------- */
+/*     4 | offset from beginning of data chunk                                */
+/*     4 | file size (uncompressed)                                           */
+/*     1 | length of filename                                                 */
+/*     * | filename (not zero terminated)                                     */
+/*                                                                            */
+/* Rest of File:                                                              */
+/*                                                                            */
+/* bytes | what                                                               */
+/* ------+------------------------------------------------------------------- */
+/*     * | data chunk                                                         */
+/*     4 | length of file total (to easily find header if file is attached to */
+/*         an executable)                                                     */
+/******************************************************************************/
+
+#ifndef GUARD_62F584E45B48B8F6069643FC44702ED5
+#define GUARD_62F584E45B48B8F6069643FC44702ED5
+
+#include "types.h"
+
+struct sw_skip {
+	u32 data_size;
+	u8 *data;
+	u16 file_count;
+	struct {
+		u32 offset;
+		u32 size;
+		char *name;
+	} *files;
+};
+
+struct sw_skip *sw_skip_create();
+struct sw_skip *sw_skip_load(char *filename);
+void sw_skip_destroy(struct sw_skip *skip);
+
+void sw_skip_save(struct sw_skip *skip, char *filename);
+
+#endif /* GUARD_62F584E45B48B8F6069643FC44702ED5 */

src/file.c

@@ -61,3 +61,78 @@ void sw_filebuffer_read(struct sw_filebuffer *buf, void *dst, u32 count) {
 	memcpy(dst, buf->_data + buf->pos, count);
 	buf->pos += count;
 }
+
+/* fwrite helpers */
+
+void sw_fwrite_u8(FILE *fil, u8 val) {
+	fwrite(&val, 1, 1, fil);
+}
+
+void sw_fwrite_i8(FILE *fil, i8 val) {
+	fwrite(&val, 1, 1, fil);
+}
+
+void sw_fwrite_u16(FILE *fil, u16 val) {
+	fwrite(&val, 1, 2, fil);
+}
+
+void sw_fwrite_i16(FILE *fil, u16 val) {
+	fwrite(&val, 1, 2, fil);
+}
+
+void sw_fwrite_u32(FILE *fil, u32 val) {
+	fwrite(&val, 1, 4, fil);
+}
+
+void sw_fwrite_i32(FILE *fil, u32 val) {
+	fwrite(&val, 1, 4, fil);
+}
+
+void sw_fwrite_u64(FILE *fil, u64 val) {
+	fwrite(&val, 1, 8, fil);
+}
+
+void sw_fwrite_i64(FILE *fil, u64 val) {
+	fwrite(&val, 1, 8, fil);
+}
+
+void sw_fwrite_f32(FILE *fil, f32 val) {
+	fwrite(&val, 1, 4, fil);
+}
+
+void sw_fwrite_f64(FILE *fil, f64 val) {
+	fwrite(&val, 1, 8, fil);
+}
+
+void sw_fwrite_bool(FILE *fil, bool val) {
+	fwrite(&val, 1, 1, fil);
+}
+
+void sw_fwrite_str_nozero(FILE *fil, char *str) {
+	fwrite(str, strlen(str), 1, fil);
+}
+
+void sw_fwrite_str_zero(FILE *fil, char *str) {
+	fwrite(str, strlen(str), 1, fil);
+	sw_fwrite_u8(fil, 0);
+}
+
+/* TODO: implement checks that string not too long? */
+
+void sw_fwrite_str_prefix8(FILE *fil, char *str) {
+	u8 size = strlen(str);
+	sw_fwrite_u8(fil, size);
+	fwrite(str, size, 1, fil);
+}
+
+void sw_fwrite_str_prefix16(FILE *fil, char *str) {
+	u16 size = strlen(str);
+	sw_fwrite_u16(fil, size);
+	fwrite(str, size, 1, fil);
+}
+
+void sw_fwrite_str_prefix32(FILE *fil, char *str) {
+	u32 size = strlen(str);
+	sw_fwrite_u32(fil, size);
+	fwrite(str, size, 1, fil);
+}

src/skip.c

@@ -0,0 +1,104 @@
+#include "skip.h"
+
+#include "error.h"
+#include "file.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct sw_skip *sw_skip_create() {
+	struct sw_skip *skip;
+
+	skip = calloc(1, sizeof(struct sw_skip));
+
+	return skip;
+}
+
+struct sw_skip *sw_skip_load(char *filename) {
+	FILE *fil;
+	struct sw_skip *skip;
+	char magic[5] = {0};
+	u8 version, compression;
+	u16 i;
+	char str[257];
+	u8 str_len;
+
+	skip = sw_skip_create();
+	fil = fopen(filename, "rb");
+
+	fread(magic, 1, 4, fil);
+	if(strcmp("SWZP", magic) != 0) {
+		sw_error("not a .skip file");
+	}
+
+	fread(&version, 1, 1, fil);
+	if(version > 0) {
+		sw_error("version %i of .skip not supported", version);
+	}
+
+	fread(&compression, 1, 1, fil);
+	if(compression > 0) {
+		sw_error("unsupported .skip compression method");
+	}
+
+	fread(&skip->data_size, 1, 4, fil);
+	fseek(fil, 4, SEEK_CUR); /* ignore compressed size */
+	fread(&skip->file_count, 1, 2, fil);
+
+	skip->files = malloc(sizeof(skip->files[0]) * skip->file_count);
+
+	for(i = 0; i < skip->file_count; ++i) {
+		memset(str, 0, 257);
+		fread(&skip->files[i].offset, 1, 4, fil);
+		fread(&skip->files[i].size, 1, 4, fil);
+		fread(&str_len, 1, 1, fil);
+		fread(str, str_len, 1, fil);
+		str[str_len] = 0;
+
+		skip->files[i].name = malloc(str_len + 1);
+		strcpy(skip->files[i].name, str);
+	}
+
+	fclose(fil);
+	return skip;
+}
+
+void sw_skip_destroy(struct sw_skip *skip) {
+	i32 i;
+
+	for(i = 0; i < skip->file_count; ++i) {
+		free(skip->files[i].name);
+	}
+	free(skip->files);
+	free(skip->data);
+	free(skip);
+}
+
+void sw_skip_save(struct sw_skip *skip, char *filename) {
+	FILE *fil;
+	u32 size;
+	u16 i;
+
+	size = 0;
+	for(i = 0; i < skip->file_count; ++i) {
+		size += skip->files[i].size;
+	}
+
+	fil = fopen(filename, "wb");
+	sw_fwrite_str_nozero(fil, "SWZP");
+	sw_fwrite_u8(fil, 0);                 /* version */
+	sw_fwrite_u8(fil, 0);                 /* compression */
+	sw_fwrite_u32(fil, size);             /* uncompressed size */
+	sw_fwrite_u32(fil, size);             /* compressed size */
+	sw_fwrite_u16(fil, skip->file_count); /* file count */
+
+	for(i = 0; i < skip->file_count; ++i) {
+		sw_fwrite_u32(fil, skip->files[i].offset);       /* offset */
+		sw_fwrite_u32(fil, skip->files[i].size);         /* file size */
+		sw_fwrite_str_prefix8(fil, skip->files[i].name); /* file name */
+	}
+
+	sw_fwrite_u32(fil, ftell(fil) + 4); /* file length */
+
+	fclose(fil);
+}