Add CBZ (comic book zip-file) parser.

2 files changed, 430 insertions, 0 deletions

diff --git a/cbz/mucbz.c b/cbz/mucbz.c
new file mode 100644
index 00000000..4a633bcb
--- /dev/null
+++ b/cbz/mucbz.c
@@ -0,0 +1,409 @@
+#include "fitz.h"
+#include "mucbz.h"
+
+#include <zlib.h>
+
+#include <ctype.h> /* for tolower */
+
+#define ZIP_LOCAL_FILE_SIG 0x04034b50
+#define ZIP_CENTRAL_DIRECTORY_SIG 0x02014b50
+#define ZIP_END_OF_CENTRAL_DIRECTORY_SIG 0x06054b50
+
+#define DPI (72.0f / 144.0f)
+
+static const char *cbz_ext_list[] = {
+	".jpg", ".jpeg", ".png",
+	".JPG", ".JPEG", ".PNG",
+	NULL
+};
+
+struct cbz_page_s
+{
+	fz_pixmap *image;
+};
+
+typedef struct cbz_entry_s cbz_entry;
+
+struct cbz_entry_s
+{
+	char *name;
+	int offset;
+};
+
+struct cbz_document_s
+{
+	fz_context *ctx;
+	fz_stream *file;
+	int entry_count;
+	cbz_entry *entry;
+	int page_count;
+	int *page;
+};
+
+static inline int getshort(fz_stream *file)
+{
+	int a = fz_read_byte(file);
+	int b = fz_read_byte(file);
+	return a | b << 8;
+}
+
+static inline int getlong(fz_stream *file)
+{
+	int a = fz_read_byte(file);
+	int b = fz_read_byte(file);
+	int c = fz_read_byte(file);
+	int d = fz_read_byte(file);
+	return a | b << 8 | c << 16 | d << 24;
+}
+
+static void *
+cbz_zip_alloc_items(void *ctx, unsigned int items, unsigned int size)
+{
+	return fz_malloc_array(ctx, items, size);
+}
+
+static void
+cbz_zip_free(void *ctx, void *ptr)
+{
+	fz_free(ctx, ptr);
+}
+
+static unsigned char *
+cbz_read_zip_entry(cbz_document *doc, int offset, int *sizep)
+{
+	fz_context *ctx = doc->ctx;
+	fz_stream *file = doc->file;
+	int sig, method, namelength, extralength;
+	unsigned long csize, usize;
+	unsigned char *cdata;
+	int code;
+
+	fz_seek(file, offset, 0);
+
+	sig = getlong(doc->file);
+	if (sig != ZIP_LOCAL_FILE_SIG)
+		fz_throw(ctx, "wrong zip local file signature (0x%x)", sig);
+
+	(void) getshort(doc->file); /* version */
+	(void) getshort(doc->file); /* general */
+	method = getshort(doc->file);
+	(void) getshort(doc->file); /* file time */
+	(void) getshort(doc->file); /* file date */
+	(void) getlong(doc->file); /* crc-32 */
+	csize = getlong(doc->file); /* csize */
+	usize = getlong(doc->file); /* usize */
+	namelength = getshort(doc->file);
+	extralength = getshort(doc->file);
+
+	fz_seek(file, namelength + extralength, 1);
+
+	cdata = fz_malloc(ctx, csize);
+	fz_try(ctx)
+	{
+		fz_read(file, cdata, csize);
+	}
+	fz_catch(ctx)
+	{
+		fz_free(ctx, cdata);
+		fz_rethrow(ctx);
+	}
+
+	if (method == 0)
+	{
+		*sizep = usize;
+		return cdata;
+	}
+
+	if (method == 8)
+	{
+		unsigned char *udata = fz_malloc(ctx, usize);
+		z_stream stream;
+
+		memset(&stream, 0, sizeof stream);
+		stream.zalloc = cbz_zip_alloc_items;
+		stream.zfree = cbz_zip_free;
+		stream.opaque = ctx;
+		stream.next_in = cdata;
+		stream.avail_in = csize;
+		stream.next_out = udata;
+		stream.avail_out = usize;
+
+		fz_try(ctx)
+		{
+			code = inflateInit2(&stream, -15);
+			if (code != Z_OK)
+				fz_throw(ctx, "zlib inflateInit2 error: %s", stream.msg);
+			code = inflate(&stream, Z_FINISH);
+			if (code != Z_STREAM_END) {
+				inflateEnd(&stream);
+				fz_throw(ctx, "zlib inflate error: %s", stream.msg);
+			}
+			code = inflateEnd(&stream);
+			if (code != Z_OK)
+				fz_throw(ctx, "zlib inflateEnd error: %s", stream.msg);
+		}
+		fz_always(ctx)
+		{
+			fz_free(ctx, cdata);
+		}
+		fz_catch(ctx)
+		{
+			fz_free(ctx, udata);
+			fz_rethrow(ctx);
+		}
+
+		*sizep = usize;
+		return udata;
+	}
+
+	fz_throw(ctx, "unknown zip method: %d", method);
+	return NULL; /* not reached */
+}
+
+static int
+cbz_compare_entries(const void *a_, const void *b_)
+{
+	const cbz_entry *a = a_;
+	const cbz_entry *b = b_;
+	return strcmp(a->name, b->name);
+}
+
+static void
+cbz_read_zip_dir_imp(cbz_document *doc, int startoffset)
+{
+	fz_context *ctx = doc->ctx;
+	fz_stream *file = doc->file;
+	int sig, offset, count;
+	int namesize, metasize, commentsize;
+	int i, k;
+
+	fz_seek(file, startoffset, 0);
+
+	sig = getlong(file);
+	if (sig != ZIP_END_OF_CENTRAL_DIRECTORY_SIG)
+		fz_throw(ctx, "wrong zip end of central directory signature (0x%x)", sig);
+
+	(void) getshort(file); /* this disk */
+	(void) getshort(file); /* start disk */
+	(void) getshort(file); /* entries in this disk */
+	count = getshort(file); /* entries in central directory disk */
+	(void) getlong(file); /* size of central directory */
+	offset = getlong(file); /* offset to central directory */
+
+	doc->entry_count = count;
+	doc->entry = fz_malloc_array(ctx, count, sizeof(cbz_entry));
+
+	fz_seek(file, offset, 0);
+
+	for (i = 0; i < count; i++)
+	{
+		cbz_entry *entry = doc->entry + i;
+
+		sig = getlong(doc->file);
+		if (sig != ZIP_CENTRAL_DIRECTORY_SIG)
+			fz_throw(doc->ctx, "wrong zip central directory signature (0x%x)", sig);
+
+		(void) getshort(file); /* version made by */
+		(void) getshort(file); /* version to extract */
+		(void) getshort(file); /* general */
+		(void) getshort(file); /* method */
+		(void) getshort(file); /* last mod file time */
+		(void) getshort(file); /* last mod file date */
+		(void) getlong(file); /* crc-32 */
+		(void) getlong(file); /* csize */
+		(void) getlong(file); /* usize */
+		namesize = getshort(file);
+		metasize = getshort(file);
+		commentsize = getshort(file);
+		(void) getshort(file); /* disk number start */
+		(void) getshort(file); /* int file atts */
+		(void) getlong(file); /* ext file atts */
+		entry->offset = getlong(file);
+
+		entry->name = malloc(namesize + 1);
+		fz_read(file, (unsigned char *)entry->name, namesize);
+		entry->name[namesize] = 0;
+
+		fz_seek(file, metasize, 1);
+		fz_seek(file, commentsize, 1);
+	}
+
+	qsort(doc->entry, count, sizeof(cbz_entry), cbz_compare_entries);
+
+	doc->page_count = 0;
+	doc->page = fz_malloc_array(ctx, count, sizeof(int));
+
+	for (i = 0; i < count; i++)
+		for (k = 0; cbz_ext_list[k]; k++)
+			if (strstr(doc->entry[i].name, cbz_ext_list[k]))
+				doc->page[doc->page_count++] = i;
+}
+
+static void
+cbz_read_zip_dir(cbz_document *doc)
+{
+	fz_stream *file = doc->file;
+	unsigned char buf[512];
+	int filesize, back, maxback;
+	int i, n;
+
+	fz_seek(file, 0, 2);
+	filesize = fz_tell(file);
+
+	maxback = MIN(filesize, 0xFFFF + sizeof buf);
+	back = MIN(maxback, sizeof buf);
+
+	while (back < maxback)
+	{
+		fz_seek(file, filesize - back, 0);
+		n = fz_read(file, buf, sizeof buf);
+		for (i = n - 4; i > 0; i--)
+		{
+			if (!memcmp(buf + i, "PK\5\6", 4))
+			{
+				cbz_read_zip_dir_imp(doc, filesize - back + i);
+				return;
+			}
+		}
+		back += sizeof buf - 4;
+	}
+
+	fz_throw(doc->ctx, "cannot find end of central directory");
+}
+
+cbz_document *
+cbz_open_document_with_stream(fz_stream *file)
+{
+	fz_context *ctx = file->ctx;
+	cbz_document *doc;
+
+	doc = fz_malloc_struct(ctx, cbz_document);
+	doc->ctx = ctx;
+	doc->file = fz_keep_stream(file);
+	doc->entry_count = 0;
+	doc->entry = NULL;
+	doc->page_count = 0;
+	doc->page = NULL;
+
+	fz_try(ctx)
+	{
+		cbz_read_zip_dir(doc);
+	}
+	fz_catch(ctx)
+	{
+		cbz_close_document(doc);
+		fz_rethrow(ctx);
+	}
+
+	return doc;
+}
+
+cbz_document *
+cbz_open_document(fz_context *ctx, char *filename)
+{
+	fz_stream *file;
+	cbz_document *doc;
+
+	file = fz_open_file(ctx, filename);
+	if (!file)
+		fz_throw(ctx, "cannot open file '%s': %s", filename, strerror(errno));
+
+	fz_try(ctx) {
+		doc = cbz_open_document_with_stream(file);
+	} fz_always(ctx) {
+		fz_close(file);
+	} fz_catch(ctx) {
+		fz_rethrow(ctx);
+	}
+
+	return doc;
+}
+
+void
+cbz_close_document(cbz_document *doc)
+{
+	int i;
+	fz_context *ctx = doc->ctx;
+	for (i = 0; i < doc->entry_count; i++)
+		fz_free(ctx, doc->entry[i].name);
+	fz_free(ctx, doc->entry);
+	fz_free(ctx, doc->page);
+	fz_close(doc->file);
+	fz_free(ctx, doc);
+}
+
+int
+cbz_count_pages(cbz_document *doc)
+{
+	return doc->page_count;
+}
+
+cbz_page *
+cbz_load_page(cbz_document *doc, int number)
+{
+	fz_context *ctx = doc->ctx;
+	unsigned char *data = NULL;
+	cbz_page *page = NULL;
+	int size;
+
+	if (number < 0 || number >= doc->page_count)
+		return NULL;
+
+	number = doc->page[number];
+
+	fz_var(data);
+	fz_var(page);
+	fz_try(ctx)
+	{
+		page = fz_malloc_struct(doc->ctx, cbz_page);
+		page->image = NULL;
+
+		data = cbz_read_zip_entry(doc, doc->entry[number].offset, &size);
+
+		if (data[0] == 0xff && data[1] == 0xd8)
+			page->image = fz_load_jpeg(ctx, data, size);
+		else if (memcmp(data, "\211PNG\r\n\032\n", 8) == 0)
+			page->image = fz_load_png(ctx, data, size);
+		else
+			fz_throw(ctx, "unknown image format");
+	}
+	fz_always(ctx)
+	{
+		fz_free(ctx, data);
+	}
+	fz_catch(ctx)
+	{
+		if (page && page->image)
+			fz_drop_pixmap(ctx, page->image);
+		fz_free(ctx, page);
+		fz_rethrow(ctx);
+	}
+
+	return page;
+}
+
+void
+cbz_free_page(cbz_document *doc, cbz_page *page)
+{
+	fz_drop_pixmap(doc->ctx, page->image);
+	fz_free(doc->ctx, page);
+}
+
+fz_rect
+cbz_bound_page(cbz_document *doc, cbz_page *page)
+{
+	fz_pixmap *image = page->image;
+	fz_rect bbox;
+	bbox.x0 = bbox.y0 = 0;
+	bbox.x1 = image->w * DPI;
+	bbox.y1 = image->h * DPI;
+	return bbox;
+}
+
+void
+cbz_run_page(cbz_document *doc, cbz_page *page, fz_device *dev, fz_matrix ctm, fz_cookie *cookie)
+{
+	fz_pixmap *image = page->image;
+	ctm = fz_concat(fz_scale(image->w * DPI, image->h * DPI), ctm);
+	fz_fill_image(dev, image, ctm, 1);
+}
diff --git a/cbz/mucbz.h b/cbz/mucbz.h
new file mode 100644
index 00000000..e18a7474
--- /dev/null
+++ b/cbz/mucbz.h
@@ -0,0 +1,21 @@
+#ifndef _MUCBZ_H_
+#define _MUCBZ_H_
+
+#ifndef _FITZ_H_
+#error "fitz.h must be included before mucbz.h"
+#endif
+
+typedef struct cbz_document_s cbz_document;
+typedef struct cbz_page_s cbz_page;
+
+cbz_document *cbz_open_document(fz_context *ctx, char *filename);
+cbz_document *cbz_open_document_with_stream(fz_stream *file);
+void cbz_close_document(cbz_document *doc);
+
+int cbz_count_pages(cbz_document *doc);
+cbz_page *cbz_load_page(cbz_document *doc, int number);
+fz_rect cbz_bound_page(cbz_document *doc, cbz_page *page);
+void cbz_free_page(cbz_document *doc, cbz_page *page);
+void cbz_run_page(cbz_document *doc, cbz_page *page, fz_device *dev, fz_matrix ctm, fz_cookie *cookie);
+
+#endif