| #ifndef PKTLINE_H |
| #define PKTLINE_H |
| |
| #include "git-compat-util.h" |
| #include "strbuf.h" |
| #include "sideband.h" |
| |
| /* |
| * Write a packetized stream, where each line is preceded by |
| * its length (including the header) as a 4-byte hex number. |
| * A length of 'zero' means end of stream (and a length of 1-3 |
| * would be an error). |
| * |
| * This is all pretty stupid, but we use this packetized line |
| * format to make a streaming format possible without ever |
| * over-running the read buffers. That way we'll never read |
| * into what might be the pack data (which should go to another |
| * process entirely). |
| * |
| * The writing side could use stdio, but since the reading |
| * side can't, we stay with pure read/write interfaces. |
| */ |
| void packet_flush(int fd); |
| void packet_delim(int fd); |
| void packet_response_end(int fd); |
| void packet_write_fmt(int fd, const char *fmt, ...) __attribute__((format (printf, 2, 3))); |
| void packet_buf_flush(struct strbuf *buf); |
| void packet_buf_delim(struct strbuf *buf); |
| void set_packet_header(char *buf, int size); |
| void packet_write(int fd_out, const char *buf, size_t size); |
| void packet_buf_write(struct strbuf *buf, const char *fmt, ...) __attribute__((format (printf, 2, 3))); |
| void packet_buf_write_len(struct strbuf *buf, const char *data, size_t len); |
| int packet_flush_gently(int fd); |
| int packet_write_fmt_gently(int fd, const char *fmt, ...) __attribute__((format (printf, 2, 3))); |
| int write_packetized_from_fd(int fd_in, int fd_out); |
| int write_packetized_from_buf(const char *src_in, size_t len, int fd_out); |
| |
| /* |
| * Read a packetized line into the buffer, which must be at least size bytes |
| * long. The return value specifies the number of bytes read into the buffer. |
| * |
| * If src_buffer and *src_buffer are not NULL, it should point to a buffer |
| * containing the packet data to parse, of at least *src_len bytes. After the |
| * function returns, src_buf will be incremented and src_len decremented by the |
| * number of bytes consumed. |
| * |
| * If src_buffer (or *src_buffer) is NULL, then data is read from the |
| * descriptor "fd". |
| * |
| * If options does not contain PACKET_READ_GENTLE_ON_EOF, we will die under any |
| * of the following conditions: |
| * |
| * 1. Read error from descriptor. |
| * |
| * 2. Protocol error from the remote (e.g., bogus length characters). |
| * |
| * 3. Receiving a packet larger than "size" bytes. |
| * |
| * 4. Truncated output from the remote (e.g., we expected a packet but got |
| * EOF, or we got a partial packet followed by EOF). |
| * |
| * If options does contain PACKET_READ_GENTLE_ON_EOF, we will not die on |
| * condition 4 (truncated input), but instead return -1. However, we will still |
| * die for the other 3 conditions. |
| * |
| * If options contains PACKET_READ_CHOMP_NEWLINE, a trailing newline (if |
| * present) is removed from the buffer before returning. |
| * |
| * If options contains PACKET_READ_DIE_ON_ERR_PACKET, it dies when it sees an |
| * ERR packet. |
| */ |
| #define PACKET_READ_GENTLE_ON_EOF (1u<<0) |
| #define PACKET_READ_CHOMP_NEWLINE (1u<<1) |
| #define PACKET_READ_DIE_ON_ERR_PACKET (1u<<2) |
| int packet_read(int fd, char **src_buffer, size_t *src_len, char |
| *buffer, unsigned size, int options); |
| |
| /* |
| * Convert a four hex digit packet line length header into its numeric |
| * representation. |
| * |
| * If lenbuf_hex contains non-hex characters, return -1. Otherwise, return the |
| * numeric value of the length header. |
| */ |
| int packet_length(const char lenbuf_hex[4]); |
| |
| /* |
| * Read a packetized line into a buffer like the 'packet_read()' function but |
| * returns an 'enum packet_read_status' which indicates the status of the read. |
| * The number of bytes read will be assigned to *pktlen if the status of the |
| * read was 'PACKET_READ_NORMAL'. |
| */ |
| enum packet_read_status { |
| PACKET_READ_EOF, |
| PACKET_READ_NORMAL, |
| PACKET_READ_FLUSH, |
| PACKET_READ_DELIM, |
| PACKET_READ_RESPONSE_END, |
| }; |
| enum packet_read_status packet_read_with_status(int fd, char **src_buffer, |
| size_t *src_len, char *buffer, |
| unsigned size, int *pktlen, |
| int options); |
| |
| /* |
| * Convenience wrapper for packet_read that is not gentle, and sets the |
| * CHOMP_NEWLINE option. The return value is NULL for a flush packet, |
| * and otherwise points to a static buffer (that may be overwritten by |
| * subsequent calls). If the size parameter is not NULL, the length of the |
| * packet is written to it. |
| */ |
| char *packet_read_line(int fd, int *size); |
| |
| /* |
| * Convenience wrapper for packet_read that sets the PACKET_READ_GENTLE_ON_EOF |
| * and CHOMP_NEWLINE options. The return value specifies the number of bytes |
| * read into the buffer or -1 on truncated input. If the *dst_line parameter |
| * is not NULL it will return NULL for a flush packet or when the number of |
| * bytes copied is zero and otherwise points to a static buffer (that may be |
| * overwritten by subsequent calls). If the size parameter is not NULL, the |
| * length of the packet is written to it. |
| */ |
| int packet_read_line_gently(int fd, int *size, char **dst_line); |
| |
| /* |
| * Same as packet_read_line, but read from a buf rather than a descriptor; |
| * see packet_read for details on how src_* is used. |
| */ |
| char *packet_read_line_buf(char **src_buf, size_t *src_len, int *size); |
| |
| /* |
| * Reads a stream of variable sized packets until a flush packet is detected. |
| */ |
| ssize_t read_packetized_to_strbuf(int fd_in, struct strbuf *sb_out); |
| |
| /* |
| * Receive multiplexed output stream over git native protocol. |
| * in_stream is the input stream from the remote, which carries data |
| * in pkt_line format with band designator. Demultiplex it into out |
| * and err and return error appropriately. Band #1 carries the |
| * primary payload. Things coming over band #2 is not necessarily |
| * error; they are usually informative message on the standard error |
| * stream, aka "verbose"). A message over band #3 is a signal that |
| * the remote died unexpectedly. A flush() concludes the stream. |
| * |
| * Returns SIDEBAND_FLUSH upon a normal conclusion, and SIDEBAND_PROTOCOL_ERROR |
| * or SIDEBAND_REMOTE_ERROR if an error occurred. |
| */ |
| int recv_sideband(const char *me, int in_stream, int out); |
| |
| struct packet_reader { |
| /* source file descriptor */ |
| int fd; |
| |
| /* source buffer and its size */ |
| char *src_buffer; |
| size_t src_len; |
| |
| /* buffer that pkt-lines are read into and its size */ |
| char *buffer; |
| unsigned buffer_size; |
| |
| /* options to be used during reads */ |
| int options; |
| |
| /* status of the last read */ |
| enum packet_read_status status; |
| |
| /* length of data read during the last read */ |
| int pktlen; |
| |
| /* the last line read */ |
| const char *line; |
| |
| /* indicates if a line has been peeked */ |
| int line_peeked; |
| |
| unsigned use_sideband : 1; |
| const char *me; |
| |
| /* hash algorithm in use */ |
| const struct git_hash_algo *hash_algo; |
| }; |
| |
| /* |
| * Initialize a 'struct packet_reader' object which is an |
| * abstraction around the 'packet_read_with_status()' function. |
| */ |
| void packet_reader_init(struct packet_reader *reader, int fd, |
| char *src_buffer, size_t src_len, |
| int options); |
| |
| /* |
| * Perform a packet read and return the status of the read. |
| * The values of 'pktlen' and 'line' are updated based on the status of the |
| * read as follows: |
| * |
| * PACKET_READ_ERROR: 'pktlen' is set to '-1' and 'line' is set to NULL |
| * PACKET_READ_NORMAL: 'pktlen' is set to the number of bytes read |
| * 'line' is set to point at the read line |
| * PACKET_READ_FLUSH: 'pktlen' is set to '0' and 'line' is set to NULL |
| */ |
| enum packet_read_status packet_reader_read(struct packet_reader *reader); |
| |
| /* |
| * Peek the next packet line without consuming it and return the status. |
| * The next call to 'packet_reader_read()' will perform a read of the same line |
| * that was peeked, consuming the line. |
| * |
| * Peeking multiple times without calling 'packet_reader_read()' will return |
| * the same result. |
| */ |
| enum packet_read_status packet_reader_peek(struct packet_reader *reader); |
| |
| #define DEFAULT_PACKET_MAX 1000 |
| #define LARGE_PACKET_MAX 65520 |
| #define LARGE_PACKET_DATA_MAX (LARGE_PACKET_MAX - 4) |
| extern char packet_buffer[LARGE_PACKET_MAX]; |
| |
| struct packet_writer { |
| int dest_fd; |
| unsigned use_sideband : 1; |
| }; |
| |
| void packet_writer_init(struct packet_writer *writer, int dest_fd); |
| |
| /* These functions die upon failure. */ |
| __attribute__((format (printf, 2, 3))) |
| void packet_writer_write(struct packet_writer *writer, const char *fmt, ...); |
| __attribute__((format (printf, 2, 3))) |
| void packet_writer_error(struct packet_writer *writer, const char *fmt, ...); |
| void packet_writer_delim(struct packet_writer *writer); |
| void packet_writer_flush(struct packet_writer *writer); |
| |
| #endif |