git-commit-vandalism/vcs-svn/line_buffer.h
Jonathan Nieder b1c9b798a6 vcs-svn: teach line_buffer about temporary files
It can sometimes be useful to write information temporarily to file,
to read back later.  These functions allow a program to use the
line_buffer facilities when doing so.

It works like this:

 1. find a unique filename with buffer_tmpfile_init.
 2. rewind with buffer_tmpfile_rewind.  This returns a stdio
    handle for writing.
 3. when finished writing, declare so with
    buffer_tmpfile_prepare_to_read.  The return value indicates
    how many bytes were written.
 4. read whatever portion of the file is needed.
 5. if finished, remove the temporary file with buffer_deinit.
    otherwise, go back to step 2,

The svn support would use this to buffer the postimage from delta
application until the length is known and fast-import can receive
the resulting blob.

Based-on-patch-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-02-26 04:59:37 -06:00

32 lines
1.0 KiB
C

#ifndef LINE_BUFFER_H_
#define LINE_BUFFER_H_
#include "strbuf.h"
#define LINE_BUFFER_LEN 10000
struct line_buffer {
char line_buffer[LINE_BUFFER_LEN];
struct strbuf blob_buffer;
FILE *infile;
};
#define LINE_BUFFER_INIT {"", STRBUF_INIT, NULL}
int buffer_init(struct line_buffer *buf, const char *filename);
int buffer_fdinit(struct line_buffer *buf, int fd);
int buffer_deinit(struct line_buffer *buf);
void buffer_reset(struct line_buffer *buf);
int buffer_tmpfile_init(struct line_buffer *buf);
FILE *buffer_tmpfile_rewind(struct line_buffer *buf); /* prepare to write. */
long buffer_tmpfile_prepare_to_read(struct line_buffer *buf);
char *buffer_read_line(struct line_buffer *buf);
char *buffer_read_string(struct line_buffer *buf, uint32_t len);
int buffer_read_char(struct line_buffer *buf);
void buffer_read_binary(struct line_buffer *buf, struct strbuf *sb, uint32_t len);
void buffer_copy_bytes(struct line_buffer *buf, uint32_t len);
void buffer_skip_bytes(struct line_buffer *buf, uint32_t len);
#endif