Initial import

1 files changed, 589 insertions, 0 deletions

diff --git a/filter/file.c b/filter/file.c
new file mode 100644
index 00000000..c3ab63a4
--- /dev/null
+++ b/filter/file.c
@@ -0,0 +1,589 @@
+#include <fitz.h>
+
+/* TODO: nil filter on write */
+
+fz_error *
+fz_ferror(fz_file *f)
+{
+	fz_error *e = f->error;
+	f->error = nil;
+	return e;
+}
+
+fz_error *
+fz_openfile(fz_file **filep, char *path, int mode)
+{
+	fz_error *error;
+	fz_file *file;
+	int fd;
+
+	assert(mode == O_RDONLY || mode == O_WRONLY);
+
+	file = *filep = fz_malloc(sizeof(fz_file));
+	if (!file)
+		return fz_outofmem;
+
+	fd = open(path, mode, 0);
+	if (fd == -1)
+		return fz_throw("ioerror: open '%s': %s", path, strerror(errno));
+
+	file->mode = mode;
+	file->fd = fd;
+	file->depth = 0;
+	file->error = nil;
+	file->filter = nil;
+	file->in = nil;
+	file->out = nil;
+
+	error = fz_newbuffer(&file->in, FZ_BUFSIZE);
+	if (error)
+		goto cleanup;
+
+	error = fz_newbuffer(&file->out, FZ_BUFSIZE);
+	if (error)
+		goto cleanup;
+
+	return nil;
+
+cleanup:
+	close(fd);
+	fz_free(file->out);
+	fz_free(file->in);
+	fz_free(file);
+	*filep = nil;
+	return error;
+}
+
+void
+fz_closefile(fz_file *file)
+{
+	assert(file->depth == 0);
+
+	if (file->mode == O_WRONLY)
+		fz_flush(file);
+
+	if (file->error)
+	{
+		fz_warn("%s", file->error->msg);
+		fz_freeerror(file->error);
+		file->error = nil;
+	}
+
+	close(file->fd);
+
+	if (file->filter) fz_freefilter(file->filter);
+	fz_freebuffer(file->in);
+	fz_freebuffer(file->out);
+	fz_free(file);
+}
+
+fz_error *
+fz_pushfilter(fz_file *file, fz_filter *filter)
+{
+	fz_error *error;
+	fz_buffer *buf;
+
+	if (file->depth == 0)
+	{
+		buf = file->out;
+		file->out = file->in;
+		file->in = buf;
+
+		file->out->rp = file->out->bp;
+		file->out->wp = file->out->bp;
+		file->out->eof = 0;
+
+		file->filter = filter;
+	}
+	else
+	{
+		error = fz_chainpipeline(&file->filter, file->filter, filter, file->out);
+		if (error)
+			return error;
+
+		error = fz_newbuffer(&file->out, FZ_BUFSIZE);
+		if (error)
+		{
+			fz_unchainpipeline(file->filter, &file->filter, &file->out);
+			return error;
+		}
+	}
+
+	file->depth ++;
+
+	return nil;
+}
+
+void
+fz_popfilter(fz_file *file)
+{
+	fz_buffer *buf;
+
+	assert(file->depth > 0);
+
+	if (file->mode == O_WRONLY)
+		fz_flush(file);
+
+	if (file->error)
+	{
+		fz_warn("%s", file->error->msg);
+		fz_freeerror(file->error);
+		file->error = nil;
+	}
+
+	if (file->depth == 1)
+	{
+		fz_freefilter(file->filter);
+		file->filter = nil;
+
+		buf = file->out;
+		file->out = file->in;
+		file->in = buf;
+
+		file->in->rp = file->in->bp;
+		file->in->wp = file->in->bp;
+		file->in->eof = 0;
+	}
+	else
+	{
+		fz_freebuffer(file->out);
+		fz_unchainpipeline(file->filter, &file->filter, &file->out);
+	}
+
+	file->depth --;
+}
+
+int
+fz_seek(fz_file *f, int ofs)
+{
+	int t;
+	int c;
+
+	assert(f->mode == O_RDONLY);
+
+	if (f->filter)
+	{
+		if (ofs < fz_tell(f))
+		{
+			f->error = fz_throw("ioerror: cannot seek backwards in filter");
+			return -1;
+		}
+		while (fz_tell(f) < ofs)
+		{
+			c = fz_readbyte(f);
+			if (c == EOF)
+				return -1;
+		}
+		return 0;
+	}
+
+	t = lseek(f->fd, ofs, 0);
+	if (t == -1)
+	{
+		f->error = fz_throw("ioerror: lseek: %s", strerror(errno));
+		return -1;
+	}
+
+	f->out->rp = f->out->bp;
+	f->out->wp = f->out->bp;
+	f->out->eof = 0;
+
+	return 0;
+}
+
+int
+fz_tell(fz_file *f)
+{
+	int t;
+
+	if (f->filter)
+	{
+		return f->filter->count - (f->out->wp - f->out->rp);
+	}
+
+	t = lseek(f->fd, 0, 1);
+	if (t == -1)
+	{
+		f->error = fz_throw("ioerror: lseek: %s", strerror(errno));
+		return -1;
+	}
+
+	return t - (f->out->wp - f->out->rp);
+}
+
+/*
+ * Read mode
+ */
+
+static int doread(fz_buffer *b, int fd)
+{
+	int n = read(fd, b->wp, b->ep - b->wp);
+	if (n == -1)
+		return -1;
+	if (n == 0)
+		b->eof = 1;
+	b->wp += n;
+	return n;
+}
+
+static int producedata(fz_file *f)
+{
+	fz_error *reason;
+	int produced;
+	int n;
+
+	assert(f->mode == O_RDONLY);
+	assert(f->error == nil);
+
+	if (!f->filter)
+	{
+		fz_rewindbuffer(f->out);
+		n = doread(f->out, f->fd);
+		if (n < 0) {
+			f->error = fz_throw("ioerror in read: %s", strerror(errno));
+			return -1;
+		}
+		return 0;
+	}
+
+	produced = 0;
+
+	while (1)
+	{
+		reason = fz_process(f->filter, f->in, f->out);
+
+		if (f->filter->produced)
+			produced = 1;
+
+		if (reason == fz_ioneedin)
+		{
+			if (f->in->eof) {
+				f->error = fz_throw("ioerror: premature eof in filter");
+				return -1;
+			}
+
+			/* no space to produce, rewind or grow */
+			if (f->in->wp == f->in->ep)
+			{
+				if (f->in->rp > f->in->bp)
+					f->error = fz_rewindbuffer(f->in);
+				else
+					f->error = fz_growbuffer(f->in);
+				if (f->error)
+					return -1;
+			}
+
+			/* then fill with more input */
+			n = doread(f->in, f->fd);
+			if (n < 0) {
+				f->error = fz_throw("ioerror in read: %s", strerror(errno));
+				return -1;
+			}
+
+			if (produced)
+				return 0;
+		}
+
+		else if (reason == fz_ioneedout)
+		{
+			if (produced)
+				return 0;
+
+			/* need more outspace, and produced no data */
+			if (f->out->rp > f->out->bp)
+				f->error = fz_rewindbuffer(f->out);
+			else
+				f->error = fz_growbuffer(f->out);
+			if (f->error)
+				return -1;
+		}
+
+		else if (reason == fz_iodone)
+			return 0;
+
+		else {
+			f->error = reason;
+			return -1;
+		}
+	}
+}
+
+int
+fz_peekbyte(fz_file *f)
+{
+	if (f->out->rp == f->out->wp)
+	{
+		if (f->out->eof) return EOF;
+		if (producedata(f)) return EOF;
+	}
+
+	if (f->out->rp < f->out->wp)
+		return *f->out->rp;
+
+	return EOF;
+}
+
+int
+fz_readbyte(fz_file *f)
+{
+	if (f->out->rp == f->out->wp)
+	{
+		if (f->out->eof) return EOF;
+		if (producedata(f)) return EOF;
+	}
+
+	if (f->out->rp < f->out->wp)
+		return *f->out->rp++;
+
+	return EOF;
+}
+
+int
+fz_read(fz_file *f, char *buf, int n)
+{
+	int i = 0;
+
+	while (i < n)
+	{
+		while (f->out->rp < f->out->wp && i < n)
+			buf[i++] = *f->out->rp ++;
+
+		if (f->out->rp == f->out->wp)
+		{
+			if (f->out->eof) return i;
+			if (producedata(f) < 0) return -1;
+		}
+	}
+
+	return i;
+}
+
+int
+fz_readline(fz_file *f, char *buf, int n)
+{
+	int c = EOF;
+	char *s = buf;
+
+	while (n > 1)
+	{
+		c = fz_readbyte(f);
+		if (c == EOF)
+			break;
+		if (c == '\r') {
+			c = fz_peekbyte(f);
+			if (c == '\n')
+				c = fz_readbyte(f);
+			break;
+		}
+		if (c == '\n')
+			break;
+		*s++ = c;
+		n--;
+	}
+	if (n)
+		*s = '\0';
+	return s - buf;
+}
+
+/*
+ * Write mode
+ */
+
+static int dowrite(fz_buffer *b, int fd)
+{
+	int n = write(fd, b->rp, b->wp - b->rp);
+	if (n == -1)
+		return -1;
+	b->rp += n;
+	return n;
+}
+
+int
+fz_write(fz_file *f, char *buf, int n)
+{
+	fz_error *reason;
+	int i = 0;
+	int x;
+
+	assert(f->mode == O_WRONLY);
+	assert(f->error == nil);
+
+	while (i < n)
+	{
+		while (f->in->rp < f->in->wp && i < n)
+		{
+			*f->in->rp++ = buf[i++];
+		}
+
+		if (f->in->rp == f->in->wp)
+		{
+			reason = fz_process(f->filter, f->in, f->out);
+
+			if (reason == fz_ioneedin)
+			{
+				if (f->in->wp == f->in->ep) {
+					if (f->in->rp > f->in->bp)
+						f->error = fz_rewindbuffer(f->in);
+					else
+						f->error = fz_growbuffer(f->in);
+					if (f->error)
+						return -1;
+				}
+			}
+
+			else if (reason == fz_ioneedout)
+			{
+				x = dowrite(f->out, f->fd);
+				if (x < 0) {
+					f->error = fz_throw("ioerror in write: %s", strerror(errno));
+					return -1;
+				}
+
+				if (f->out->rp > f->out->bp)
+					f->error = fz_rewindbuffer(f->out);
+				else
+					f->error = fz_growbuffer(f->out);
+				if (f->error)
+					return -1;
+			}
+
+			else if (reason == fz_iodone)
+			{
+				x = dowrite(f->out, f->fd);
+				if (x < 0) {
+					f->error = fz_throw("ioerror in write: %s", strerror(errno));
+					return -1;
+				}
+				break;
+			}
+
+			else {
+				f->error = reason;
+				return -1;
+			}
+		}
+	}
+
+	return i;
+}
+
+int
+fz_flush(fz_file *f)
+{
+	fz_error *reason;
+	int n;
+
+	assert(f->mode == O_WRONLY);
+	assert(f->error == nil);
+
+	f->in->eof = 1;
+
+	while (!f->out->eof)
+	{
+		reason = fz_process(f->filter, f->in, f->out);
+
+		if (reason == fz_ioneedin) {
+			f->error = fz_throw("ioerror: premature eof in filter");
+			return -1;
+		}
+
+		else if (reason == fz_ioneedout)
+		{
+			n = dowrite(f->out, f->fd);
+			if (n < 0) {
+				f->error = fz_throw("ioerror in write: %s", strerror(errno));
+				return -1;
+			}
+
+			if (f->out->rp > f->out->bp)
+				f->error = fz_rewindbuffer(f->out);
+			else
+				f->error = fz_growbuffer(f->out);
+			if (f->error)
+				return -1;
+		}
+
+		else if (reason == fz_iodone)
+		{
+			n = dowrite(f->out, f->fd);
+			if (n < 0) {
+				f->error = fz_throw("ioerror in write: %s", strerror(errno));
+				return -1;
+			}
+			break;
+		}
+
+		else {
+			f->error = reason;
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Utility function to consume contents of file stream into
+ * a freshly allocated buffer; realloced and trimmed to size.
+ */
+
+enum { CHUNKSIZE = 4096 };
+
+fz_error *
+fz_readfile(unsigned char **bufp, int *lenp, fz_file *file)
+{
+	unsigned char *newbuf;
+	unsigned char *buf;
+	int len;
+	int pos;
+	int n;
+
+	*bufp = nil;
+	*lenp = 0;
+
+	len = 0;
+	pos = 0;
+	buf = nil;
+
+	while (1)
+	{
+		if (len - pos == 0)
+		{
+			len += CHUNKSIZE;
+			newbuf = fz_realloc(buf, len);
+			if (!newbuf)
+			{
+				fz_free(buf);
+				return fz_outofmem;
+			}
+			buf = newbuf;
+		}
+
+		n = fz_read(file, buf + pos, len - pos);
+
+printf("fz_read %d bytes\n", n);
+
+		if (n < 0)
+		{
+			fz_free(buf);
+			return fz_ferror(file);
+		}
+
+		pos += n;
+
+		if (n < CHUNKSIZE)
+		{
+			newbuf = fz_realloc(buf, pos);
+			if (!newbuf)
+			{
+				fz_free(buf);
+				return fz_outofmem;
+			}
+
+			*bufp = newbuf;
+			*lenp = pos;
+			return nil;
+		}
+	}
+}
+