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 */ 22voidpacket_flush(int fd); 23voidpacket_write_fmt(int fd,const char*fmt, ...)__attribute__((format(printf,2,3))); 24voidpacket_buf_flush(struct strbuf *buf); 25voidpacket_buf_write(struct strbuf *buf,const char*fmt, ...)__attribute__((format(printf,2,3))); 26intpacket_write_fmt_gently(int fd,const char*fmt, ...)__attribute__((format(printf,2,3))); 27 28/* 29 * Read a packetized line into the buffer, which must be at least size bytes 30 * long. The return value specifies the number of bytes read into the buffer. 31 * 32 * If src_buffer and *src_buffer are not NULL, it should point to a buffer 33 * containing the packet data to parse, of at least *src_len bytes. After the 34 * function returns, src_buf will be incremented and src_len decremented by the 35 * number of bytes consumed. 36 * 37 * If src_buffer (or *src_buffer) is NULL, then data is read from the 38 * descriptor "fd". 39 * 40 * If options does not contain PACKET_READ_GENTLE_ON_EOF, we will die under any 41 * of the following conditions: 42 * 43 * 1. Read error from descriptor. 44 * 45 * 2. Protocol error from the remote (e.g., bogus length characters). 46 * 47 * 3. Receiving a packet larger than "size" bytes. 48 * 49 * 4. Truncated output from the remote (e.g., we expected a packet but got 50 * EOF, or we got a partial packet followed by EOF). 51 * 52 * If options does contain PACKET_READ_GENTLE_ON_EOF, we will not die on 53 * condition 4 (truncated input), but instead return -1. However, we will still 54 * die for the other 3 conditions. 55 * 56 * If options contains PACKET_READ_CHOMP_NEWLINE, a trailing newline (if 57 * present) is removed from the buffer before returning. 58 */ 59#define PACKET_READ_GENTLE_ON_EOF (1u<<0) 60#define PACKET_READ_CHOMP_NEWLINE (1u<<1) 61intpacket_read(int fd,char**src_buffer,size_t*src_len,char 62*buffer,unsigned size,int options); 63 64/* 65 * Convenience wrapper for packet_read that is not gentle, and sets the 66 * CHOMP_NEWLINE option. The return value is NULL for a flush packet, 67 * and otherwise points to a static buffer (that may be overwritten by 68 * subsequent calls). If the size parameter is not NULL, the length of the 69 * packet is written to it. 70 */ 71char*packet_read_line(int fd,int*size); 72 73/* 74 * Same as packet_read_line, but read from a buf rather than a descriptor; 75 * see packet_read for details on how src_* is used. 76 */ 77char*packet_read_line_buf(char**src_buf,size_t*src_len,int*size); 78 79#define DEFAULT_PACKET_MAX 1000 80#define LARGE_PACKET_MAX 65520 81externchar packet_buffer[LARGE_PACKET_MAX]; 82 83#endif