 74cf249d5c
			
		
	
	
	74cf249d5c
	
	
	
		
			
			Several areas already used this technique, so do some audit to consistently use it elsewhere. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-9sbere0kkplwe45ak6rk4a1f@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
		
			
				
	
	
		
			134 lines
		
	
	
	
		
			2.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			134 lines
		
	
	
	
		
			2.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| #include "cache.h"
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| #include <linux/kernel.h>
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| 
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| int prefixcmp(const char *str, const char *prefix)
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| {
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| 	for (; ; str++, prefix++)
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| 		if (!*prefix)
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| 			return 0;
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| 		else if (*str != *prefix)
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| 			return (unsigned char)*prefix - (unsigned char)*str;
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| }
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| 
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| /*
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|  * Used as the default ->buf value, so that people can always assume
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|  * buf is non NULL and ->buf is NUL terminated even for a freshly
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|  * initialized strbuf.
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|  */
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| char strbuf_slopbuf[1];
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| 
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| void strbuf_init(struct strbuf *sb, ssize_t hint)
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| {
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| 	sb->alloc = sb->len = 0;
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| 	sb->buf = strbuf_slopbuf;
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| 	if (hint)
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| 		strbuf_grow(sb, hint);
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| }
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| 
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| void strbuf_release(struct strbuf *sb)
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| {
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| 	if (sb->alloc) {
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| 		zfree(&sb->buf);
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| 		strbuf_init(sb, 0);
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| 	}
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| }
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| 
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| char *strbuf_detach(struct strbuf *sb, size_t *sz)
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| {
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| 	char *res = sb->alloc ? sb->buf : NULL;
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| 	if (sz)
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| 		*sz = sb->len;
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| 	strbuf_init(sb, 0);
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| 	return res;
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| }
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| 
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| void strbuf_grow(struct strbuf *sb, size_t extra)
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| {
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| 	if (sb->len + extra + 1 <= sb->len)
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| 		die("you want to use way too much memory");
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| 	if (!sb->alloc)
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| 		sb->buf = NULL;
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| 	ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
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| }
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| 
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| static void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
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| 				   const void *data, size_t dlen)
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| {
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| 	if (pos + len < pos)
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| 		die("you want to use way too much memory");
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| 	if (pos > sb->len)
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| 		die("`pos' is too far after the end of the buffer");
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| 	if (pos + len > sb->len)
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| 		die("`pos + len' is too far after the end of the buffer");
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| 
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| 	if (dlen >= len)
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| 		strbuf_grow(sb, dlen - len);
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| 	memmove(sb->buf + pos + dlen,
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| 			sb->buf + pos + len,
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| 			sb->len - pos - len);
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| 	memcpy(sb->buf + pos, data, dlen);
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| 	strbuf_setlen(sb, sb->len + dlen - len);
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| }
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| 
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| void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
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| {
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| 	strbuf_splice(sb, pos, len, NULL, 0);
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| }
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| 
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| void strbuf_add(struct strbuf *sb, const void *data, size_t len)
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| {
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| 	strbuf_grow(sb, len);
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| 	memcpy(sb->buf + sb->len, data, len);
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| 	strbuf_setlen(sb, sb->len + len);
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| }
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| 
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| void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
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| {
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| 	int len;
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| 	va_list ap;
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| 
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| 	if (!strbuf_avail(sb))
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| 		strbuf_grow(sb, 64);
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| 	va_start(ap, fmt);
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| 	len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
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| 	va_end(ap);
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| 	if (len < 0)
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| 		die("your vsnprintf is broken");
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| 	if (len > strbuf_avail(sb)) {
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| 		strbuf_grow(sb, len);
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| 		va_start(ap, fmt);
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| 		len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
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| 		va_end(ap);
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| 		if (len > strbuf_avail(sb)) {
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| 			die("this should not happen, your vsnprintf is broken");
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| 		}
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| 	}
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| 	strbuf_setlen(sb, sb->len + len);
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| }
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| 
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| ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint)
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| {
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| 	size_t oldlen = sb->len;
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| 	size_t oldalloc = sb->alloc;
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| 
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| 	strbuf_grow(sb, hint ? hint : 8192);
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| 	for (;;) {
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| 		ssize_t cnt;
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| 
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| 		cnt = read(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
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| 		if (cnt < 0) {
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| 			if (oldalloc == 0)
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| 				strbuf_release(sb);
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| 			else
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| 				strbuf_setlen(sb, oldlen);
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| 			return -1;
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| 		}
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| 		if (!cnt)
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| 			break;
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| 		sb->len += cnt;
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| 		strbuf_grow(sb, 8192);
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| 	}
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| 
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| 	sb->buf[sb->len] = '\0';
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| 	return sb->len - oldlen;
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| }
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