1#ifndef PKTLINE_H 2#define PKTLINE_H 3 4#include "git-compat-util.h" 5#include "strbuf.h" 6 7/* 8 * Write a packetized stream, where each line is preceded by 9 * its length (including the header) as a 4-byte hex number. 10 * A length of 'zero' means end of stream (and a length of 1-3 11 * would be an error). 12 * 13 * This is all pretty stupid, but we use this packetized line 14 * format to make a streaming format possible without ever 15 * over-running the read buffers. That way we'll never read 16 * into what might be the pack data (which should go to another 17 * process entirely). 18 * 19 * The writing side could use stdio, but since the reading 20 * side can't, we stay with pure read/write interfaces. 21 */ 22void packet_flush(int fd); 23void packet_write(int fd, const char *fmt, ...) __attribute__((format (printf, 2, 3))); 24void packet_buf_flush(struct strbuf *buf); 25void packet_buf_write(struct strbuf *buf, const char *fmt, ...) __attribute__((format (printf, 2, 3))); 26 27/* 28 * Read a packetized line from the descriptor into the buffer, which must be at 29 * least size bytes long. The return value specifies the number of bytes read 30 * into the buffer. 31 * 32 * If options does not contain PACKET_READ_GENTLE_ON_EOF, we will die under any 33 * of the following conditions: 34 * 35 * 1. Read error from descriptor. 36 * 37 * 2. Protocol error from the remote (e.g., bogus length characters). 38 * 39 * 3. Receiving a packet larger than "size" bytes. 40 * 41 * 4. Truncated output from the remote (e.g., we expected a packet but got 42 * EOF, or we got a partial packet followed by EOF). 43 * 44 * If options does contain PACKET_READ_GENTLE_ON_EOF, we will not die on 45 * condition 4 (truncated input), but instead return -1. However, we will still 46 * die for the other 3 conditions. 47 * 48 * If options contains PACKET_READ_CHOMP_NEWLINE, a trailing newline (if 49 * present) is removed from the buffer before returning. 50 */ 51#define PACKET_READ_GENTLE_ON_EOF (1u<<0) 52#define PACKET_READ_CHOMP_NEWLINE (1u<<1) 53int packet_read(int fd, char *buffer, unsigned size, int options); 54 55/* 56 * Convenience wrapper for packet_read that is not gentle, and sets the 57 * CHOMP_NEWLINE option. 58 */ 59int packet_read_line(int fd, char *buffer, unsigned size); 60 61#define DEFAULT_PACKET_MAX 1000 62#define LARGE_PACKET_MAX 65520 63 64int packet_get_line(struct strbuf *out, char **src_buf, size_t *src_len); 65 66#endif