 d824cbba02
			
		
	
	d824cbba02
	
	
	
		
			
			Change calls to die(..., strerror(errno)) to use the new die_errno(). In the process, also make slight style adjustments: at least state _something_ about the function that failed (instead of just printing the pathname), and put paths in single quotes. Signed-off-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
		
			
				
	
	
		
			110 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			110 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include "cache.h"
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| #include "pkt-line.h"
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| 
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| /*
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|  * Write a packetized stream, where each line is preceded by
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|  * its length (including the header) as a 4-byte hex number.
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|  * A length of 'zero' means end of stream (and a length of 1-3
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|  * would be an error).
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|  *
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|  * This is all pretty stupid, but we use this packetized line
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|  * format to make a streaming format possible without ever
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|  * over-running the read buffers. That way we'll never read
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|  * into what might be the pack data (which should go to another
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|  * process entirely).
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|  *
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|  * The writing side could use stdio, but since the reading
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|  * side can't, we stay with pure read/write interfaces.
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|  */
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| ssize_t safe_write(int fd, const void *buf, ssize_t n)
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| {
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| 	ssize_t nn = n;
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| 	while (n) {
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| 		int ret = xwrite(fd, buf, n);
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| 		if (ret > 0) {
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| 			buf = (char *) buf + ret;
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| 			n -= ret;
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| 			continue;
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| 		}
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| 		if (!ret)
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| 			die("write error (disk full?)");
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| 		die_errno("write error");
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| 	}
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| 	return nn;
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| }
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| 
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| /*
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|  * If we buffered things up above (we don't, but we should),
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|  * we'd flush it here
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|  */
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| void packet_flush(int fd)
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| {
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| 	safe_write(fd, "0000", 4);
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| }
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| 
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| #define hex(a) (hexchar[(a) & 15])
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| void packet_write(int fd, const char *fmt, ...)
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| {
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| 	static char buffer[1000];
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| 	static char hexchar[] = "0123456789abcdef";
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| 	va_list args;
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| 	unsigned n;
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| 
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| 	va_start(args, fmt);
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| 	n = vsnprintf(buffer + 4, sizeof(buffer) - 4, fmt, args);
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| 	va_end(args);
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| 	if (n >= sizeof(buffer)-4)
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| 		die("protocol error: impossibly long line");
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| 	n += 4;
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| 	buffer[0] = hex(n >> 12);
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| 	buffer[1] = hex(n >> 8);
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| 	buffer[2] = hex(n >> 4);
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| 	buffer[3] = hex(n);
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| 	safe_write(fd, buffer, n);
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| }
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| 
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| static void safe_read(int fd, void *buffer, unsigned size)
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| {
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| 	ssize_t ret = read_in_full(fd, buffer, size);
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| 	if (ret < 0)
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| 		die_errno("read error");
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| 	else if (ret < size)
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| 		die("The remote end hung up unexpectedly");
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| }
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| 
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| int packet_read_line(int fd, char *buffer, unsigned size)
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| {
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| 	int n;
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| 	unsigned len;
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| 	char linelen[4];
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| 
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| 	safe_read(fd, linelen, 4);
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| 
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| 	len = 0;
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| 	for (n = 0; n < 4; n++) {
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| 		unsigned char c = linelen[n];
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| 		len <<= 4;
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| 		if (c >= '0' && c <= '9') {
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| 			len += c - '0';
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| 			continue;
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| 		}
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| 		if (c >= 'a' && c <= 'f') {
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| 			len += c - 'a' + 10;
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| 			continue;
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| 		}
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| 		if (c >= 'A' && c <= 'F') {
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| 			len += c - 'A' + 10;
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| 			continue;
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| 		}
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| 		die("protocol error: bad line length character");
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| 	}
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| 	if (!len)
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| 		return 0;
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| 	len -= 4;
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| 	if (len >= size)
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| 		die("protocol error: bad line length %d", len);
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| 	safe_read(fd, buffer, len);
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| 	buffer[len] = 0;
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| 	return len;
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| }
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