1 files changed, 390 insertions, 0 deletions
diff --git a/source/fitz/buffer.c b/source/fitz/buffer.c
new file mode 100644
index 00000000..388e0461
--- /dev/null
+++ b/source/fitz/buffer.c
@@ -0,0 +1,390 @@
+#include "mupdf/fitz.h"
+
+fz_buffer *
+fz_new_buffer(fz_context *ctx, int size)
+{
+	fz_buffer *b;
+
+	size = size > 1 ? size : 16;
+
+	b = fz_malloc_struct(ctx, fz_buffer);
+	b->refs = 1;
+	fz_try(ctx)
+	{
+		b->data = fz_malloc(ctx, size);
+	}
+	fz_catch(ctx)
+	{
+		fz_free(ctx, b);
+		fz_rethrow(ctx);
+	}
+	b->cap = size;
+	b->len = 0;
+	b->unused_bits = 0;
+
+	return b;
+}
+
+fz_buffer *
+fz_new_buffer_from_data(fz_context *ctx, unsigned char *data, int size)
+{
+	fz_buffer *b;
+
+	b = fz_malloc_struct(ctx, fz_buffer);
+	b->refs = 1;
+	b->data = data;
+	b->cap = size;
+	b->len = size;
+	b->unused_bits = 0;
+
+	return b;
+}
+
+fz_buffer *
+fz_keep_buffer(fz_context *ctx, fz_buffer *buf)
+{
+	if (buf)
+	{
+		if (buf->refs == 1 && buf->cap > buf->len+1)
+			fz_resize_buffer(ctx, buf, buf->len);
+		buf->refs ++;
+	}
+
+	return buf;
+}
+
+void
+fz_drop_buffer(fz_context *ctx, fz_buffer *buf)
+{
+	if (!buf)
+		return;
+	if (--buf->refs == 0)
+	{
+		fz_free(ctx, buf->data);
+		fz_free(ctx, buf);
+	}
+}
+
+void
+fz_resize_buffer(fz_context *ctx, fz_buffer *buf, int size)
+{
+	buf->data = fz_resize_array(ctx, buf->data, size, 1);
+	buf->cap = size;
+	if (buf->len > buf->cap)
+		buf->len = buf->cap;
+}
+
+void
+fz_grow_buffer(fz_context *ctx, fz_buffer *buf)
+{
+	int newsize = (buf->cap * 3) / 2;
+	if (newsize == 0)
+		newsize = 256;
+	fz_resize_buffer(ctx, buf, newsize);
+}
+
+static void
+fz_ensure_buffer(fz_context *ctx, fz_buffer *buf, int min)
+{
+	int newsize = buf->cap;
+	while (newsize < min)
+	{
+		newsize = (newsize * 3) / 2;
+	}
+	fz_resize_buffer(ctx, buf, newsize);
+}
+
+void
+fz_trim_buffer(fz_context *ctx, fz_buffer *buf)
+{
+	if (buf->cap > buf->len+1)
+		fz_resize_buffer(ctx, buf, buf->len);
+}
+
+int
+fz_buffer_storage(fz_context *ctx, fz_buffer *buf, unsigned char **datap)
+{
+	if (datap)
+		*datap = (buf ? buf->data : NULL);
+	return (buf ? buf->len : 0);
+}
+
+void
+fz_buffer_cat(fz_context *ctx, fz_buffer *buf, fz_buffer *extra)
+{
+	if (buf->cap - buf->len < extra->len)
+	{
+		buf->data = fz_resize_array(ctx, buf->data, buf->len + extra->len, 1);
+		buf->cap = buf->len + extra->len;
+	}
+
+	memcpy(buf->data + buf->len, extra->data, extra->len);
+	buf->len += extra->len;
+}
+
+void fz_write_buffer(fz_context *ctx, fz_buffer *buf, const void *data, int len)
+{
+	if (buf->len + len > buf->cap)
+		fz_ensure_buffer(ctx, buf, buf->len + len);
+	memcpy(buf->data + buf->len, data, len);
+	buf->len += len;
+	buf->unused_bits = 0;
+}
+
+void fz_write_buffer_byte(fz_context *ctx, fz_buffer *buf, int val)
+{
+	if (buf->len > buf->cap)
+		fz_grow_buffer(ctx, buf);
+	buf->data[buf->len++] = val;
+	buf->unused_bits = 0;
+}
+
+void fz_write_buffer_rune(fz_context *ctx, fz_buffer *buf, int c)
+{
+	char data[10];
+	int len = fz_runetochar(data, c);
+	if (buf->len + len > buf->cap)
+		fz_ensure_buffer(ctx, buf, buf->len + len);
+	memcpy(buf->data + buf->len, data, len);
+	buf->len += len;
+	buf->unused_bits = 0;
+}
+
+void fz_write_buffer_bits(fz_context *ctx, fz_buffer *buf, int val, int bits)
+{
+	int shift;
+
+	/* Throughout this code, the invariant is that we need to write the
+	 * bottom 'bits' bits of 'val' into the stream. On entry we assume
+	 * that val & ((1<<bits)-1) == val, but we do not rely on this after
+	 * having written the first partial byte. */
+
+	if (bits == 0)
+		return;
+
+	/* buf->len always covers all the bits in the buffer, including
+	 * any unused ones in the last byte, which will always be 0.
+	 * buf->unused_bits = the number of unused bits in the last byte.
+	 */
+
+	/* Find the amount we need to shift val up by so that it will be in
+	 * the correct position to be inserted into any existing data byte. */
+	shift = (buf->unused_bits - bits);
+
+	/* Extend the buffer as required before we start; that way we never
+	 * fail part way during writing. If shift < 0, then we'll need -shift
+	 * more bits. */
+	if (shift < 0)
+	{
+		int extra = (7-shift)>>3; /* Round up to bytes */
+		fz_ensure_buffer(ctx, buf, buf->len + extra);
+	}
+
+	/* Write any bits that will fit into the existing byte */
+	if (buf->unused_bits)
+	{
+		buf->data[buf->len-1] |= (shift >= 0 ? (((unsigned int)val)<<shift) : (((unsigned int)val)>>-shift));
+		if (shift >= 0)
+		{
+			/* If we were shifting up, we're done. */
+			buf->unused_bits -= bits;
+			return;
+		}
+		/* The number of bits left to write is the number that didn't
+		 * fit in this first byte. */
+		bits = -shift;
+	}
+
+	/* Write any whole bytes */
+	while (bits >= 8)
+	{
+		bits -= 8;
+		buf->data[buf->len++] = val>>bits;
+	}
+
+	/* Write trailing bits (with 0's in unused bits) */
+	if (bits > 0)
+	{
+		bits = 8-bits;
+		buf->data[buf->len++] = val<<bits;
+	}
+	buf->unused_bits = bits;
+}
+
+void fz_write_buffer_pad(fz_context *ctx, fz_buffer *buf)
+{
+	buf->unused_bits = 0;
+}
+
+int
+fz_buffer_printf(fz_context *ctx, fz_buffer *buffer, const char *fmt, ...)
+{
+	int ret;
+	va_list args;
+	va_start(args, fmt);
+
+	ret = fz_buffer_vprintf(ctx, buffer, fmt, args);
+
+	va_end(args);
+
+	return ret;
+}
+
+int
+fz_buffer_vprintf(fz_context *ctx, fz_buffer *buffer, const char *fmt, va_list old_args)
+{
+	int len;
+
+	do
+	{
+		int slack = buffer->cap - buffer->len;
+
+		if (slack > 0)
+		{
+			va_list args;
+#ifdef _MSC_VER /* Microsoft Visual C */
+			args = old_args;
+#else
+			va_copy(args, old_args);
+#endif
+			len = vsnprintf((char *)buffer->data + buffer->len, slack, fmt, args);
+#ifndef _MSC_VER
+			va_end(args);
+#endif
+			/* len = number of chars written, not including the terminating
+			 * NULL, so len+1 > slack means "truncated". MSVC differs here
+			 * and returns -1 for truncated. */
+			if (len >= 0 && len+1 <= slack)
+				break;
+		}
+		/* Grow the buffer and retry */
+		fz_grow_buffer(ctx, buffer);
+	}
+	while (1);
+
+	buffer->len += len;
+
+	return len;
+}
+
+void
+fz_buffer_cat_pdf_string(fz_context *ctx, fz_buffer *buffer, const char *text)
+{
+	int len = 2;
+	const char *s = text;
+	char *d;
+	char c;
+
+	while ((c = *s++) != 0)
+	{
+		switch (c)
+		{
+		case '\n':
+		case '\r':
+		case '\t':
+		case '\b':
+		case '\f':
+		case '(':
+		case ')':
+		case '\\':
+			len++;
+			break;
+		}
+		len++;
+	}
+
+	while(buffer->cap - buffer->len < len)
+		fz_grow_buffer(ctx, buffer);
+
+	s = text;
+	d = (char *)buffer->data + buffer->len;
+	*d++ = '(';
+	while ((c = *s++) != 0)
+	{
+		switch (c)
+		{
+		case '\n':
+			*d++ = '\\';
+			*d++ = 'n';
+			break;
+		case '\r':
+			*d++ = '\\';
+			*d++ = 'r';
+			break;
+		case '\t':
+			*d++ = '\\';
+			*d++ = 't';
+			break;
+		case '\b':
+			*d++ = '\\';
+			*d++ = 'b';
+			break;
+		case '\f':
+			*d++ = '\\';
+			*d++ = 'f';
+			break;
+		case '(':
+			*d++ = '\\';
+			*d++ = '(';
+			break;
+		case ')':
+			*d++ = '\\';
+			*d++ = ')';
+			break;
+		case '\\':
+			*d++ = '\\';
+			*d++ = '\\';
+			break;
+		default:
+			*d++ = c;
+		}
+	}
+	*d++ = ')';
+	buffer->len += len;
+}
+
+#ifdef TEST_BUFFER_WRITE
+
+#define TEST_LEN 1024
+
+void
+fz_test_buffer_write(fz_context *ctx)
+{
+	fz_buffer *master = fz_new_buffer(ctx, TEST_LEN);
+	fz_buffer *copy = fz_new_buffer(ctx, TEST_LEN);
+	fz_stream *stm;
+	int i, j, k;
+
+	/* Make us a dummy buffer */
+	for (i = 0; i < TEST_LEN; i++)
+	{
+		master->data[i] = rand();
+	}
+	master->len = TEST_LEN;
+
+	/* Now copy that buffer several times, checking it for validity */
+	stm = fz_open_buffer(ctx, master);
+	for (i = 0; i < 256; i++)
+	{
+		memset(copy->data, i, TEST_LEN);
+		copy->len = 0;
+		j = TEST_LEN * 8;
+		do
+		{
+			k = (rand() & 31)+1;
+			if (k > j)
+				k = j;
+			fz_write_buffer_bits(ctx, copy, fz_read_bits(stm, k), k);
+			j -= k;
+		}
+		while (j);
+
+		if (memcmp(copy->data, master->data, TEST_LEN) != 0)
+			fprintf(stderr, "Copied buffer is different!\n");
+		fz_seek(stm, 0, 0);
+	}
+	fz_close(stm);
+	fz_drop_buffer(ctx, master);
+	fz_drop_buffer(ctx, copy);
+}
+#endif