X-Git-Url: https://git.decadent.org.uk/gitweb/?p=nfs-utils.git;a=blobdiff_plain;f=support%2Fnfs%2Fcacheio.c;h=6a6ed5ac7f093a590e621895a03f2c9e3729683e;hp=20d195c16ca4b792fbb7b7866688e7993ab87db8;hb=965b4cf6398bed2a2c722b9d632b9674c228e36c;hpb=e09fbc8933961a0a774217ef32d73da373ddc670

diff --git a/support/nfs/cacheio.c b/support/nfs/cacheio.c
index 20d195c..6a6ed5a 100644
--- a/support/nfs/cacheio.c
+++ b/support/nfs/cacheio.c
@@ -17,12 +17,14 @@
 
 #include <nfslib.h>
 #include <stdio.h>
+#include <stdio_ext.h>
 #include <ctype.h>
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <time.h>
+#include <errno.h>
 
 void qword_add(char **bpp, int *lp, char *str)
 {
@@ -87,13 +89,47 @@ void qword_addhex(char **bpp, int *lp, char *buf, int blen)
 	*lp = len;
 }
 
+void qword_addint(char **bpp, int *lp, int n)
+{
+	int len;
+
+	len = snprintf(*bpp, *lp, "%d ", n);
+	if (len > *lp)
+		len = *lp;
+	*bpp += len;
+	*lp -= len;
+}
+
+void qword_adduint(char **bpp, int *lp, unsigned int n)
+{
+	int len;
+
+	len = snprintf(*bpp, *lp, "%u ", n);
+	if (len > *lp)
+		len = *lp;
+	*bpp += len;
+	*lp -= len;
+}
+
+void qword_addeol(char **bpp, int *lp)
+{
+	if (*lp <= 0)
+		return;
+	**bpp = '\n';
+	(*bpp)++;
+	(*lp)--;
+}
+
 static char qword_buf[8192];
 void qword_print(FILE *f, char *str)
 {
 	char *bp = qword_buf;
 	int len = sizeof(qword_buf);
 	qword_add(&bp, &len, str);
-	fwrite(qword_buf, bp-qword_buf, 1, f);
+	if (fwrite(qword_buf, bp-qword_buf, 1, f) != 1) {
+		xlog_warn("qword_print: fwrite failed: errno %d (%s)",
+			errno, strerror(errno));
+	}
 }
 
 void qword_printhex(FILE *f, char *str, int slen)
@@ -101,7 +137,10 @@ void qword_printhex(FILE *f, char *str, int slen)
 	char *bp = qword_buf;
 	int len = sizeof(qword_buf);
 	qword_addhex(&bp, &len, str, slen);
-	fwrite(qword_buf, bp-qword_buf, 1, f);
+	if (fwrite(qword_buf, bp-qword_buf, 1, f) != 1) {
+		xlog_warn("qword_printhex: fwrite failed: errno %d (%s)",
+			errno, strerror(errno));
+	}
 }
 
 void qword_printint(FILE *f, int num)
@@ -109,10 +148,27 @@ void qword_printint(FILE *f, int num)
 	fprintf(f, "%d ", num);
 }
 
-void qword_eol(FILE *f)
+int qword_eol(FILE *f)
 {
+	int err;
+
 	fprintf(f,"\n");
+	err = fflush(f);
+	if (err) {
+		xlog_warn("qword_eol: fflush failed: errno %d (%s)",
+			    errno, strerror(errno));
+	}
+	/*
+	 * We must send one line (and one line only) in a single write
+	 * call.  In case of a write error, libc may accumulate the
+	 * unwritten data and try to write it again later, resulting in a
+	 * multi-line write.  So we must explicitly ask it to throw away
+	 * any such cached data.  But we return any original error
+	 * indication to the caller.
+	 */
+	__fpurge(f);
 	fflush(f);
+	return err;
 }
 
 
@@ -180,23 +236,25 @@ int qword_get_int(char **bpp, int *anint)
 	return 0;
 }
 
+#define READLINE_BUFFER_INCREMENT 2048
+
 int readline(int fd, char **buf, int *lenp)
 {
 	/* read a line into *buf, which is malloced *len long
 	 * realloc if needed until we find a \n
 	 * nul out the \n and return
-	 * 0 of eof, 1 of success 
+	 * 0 on eof, 1 on success
 	 */
-	int len = *lenp;
+	int len;
 
-	if (len == 0) {
-		char *b = malloc(128);
+	if (*lenp == 0) {
+		char *b = malloc(READLINE_BUFFER_INCREMENT);
 		if (b == NULL)
 			return 0;
 		*buf = b;
-		*lenp = 128;
+		*lenp = READLINE_BUFFER_INCREMENT;
 	}
-	len = read(fd, *buf, len);
+	len = read(fd, *buf, *lenp);
 	if (len <= 0)
 		return 0;
 	while ((*buf)[len-1] != '\n') {
@@ -205,16 +263,17 @@ int readline(int fd, char **buf, int *lenp)
 	 */
 		char *new;
 		int nl;
-		*lenp += 128;
+		*lenp += READLINE_BUFFER_INCREMENT;
 		new = realloc(*buf, *lenp);
 		if (new == NULL)
 			return 0;
-		nl = read(fd, *buf +len, *lenp - len);
-		if (nl <= 0 )
+		*buf = new;
+		nl = read(fd, *buf + len, *lenp - len);
+		if (nl <= 0)
 			return 0;
-		new += nl;
+		len += nl;
 	}
-	(*buf)[len-1] = 0;
+	(*buf)[len-1] = '\0';
 	return 1;
 }
 
@@ -246,15 +305,25 @@ cache_flush(int force)
 	int c;
 	char stime[20];
 	char path[200];
+	time_t now;
+	/* Note: the order of these caches is important.
+	 * They need to be flushed in dependancy order. So
+	 * a cache that references items in another cache,
+	 * as nfsd.fh entries reference items in nfsd.export,
+	 * must be flushed before the cache that it references.
+	 */
 	static char *cachelist[] = {
 		"auth.unix.ip",
-		"nfsd.export",
+		"auth.unix.gid",
 		"nfsd.fh",
+		"nfsd.export",
 		NULL
 	};
-	stb.st_mtime = time(0);
-	if (!force)
-		stat(_PATH_ETAB, &stb);
+	now = time(0);
+	if (force ||
+	    stat(_PATH_ETAB, &stb) != 0 ||
+	    stb.st_mtime > now)
+		stb.st_mtime = time(0);
 	
 	sprintf(stime, "%ld\n", stb.st_mtime);
 	for (c=0; cachelist[c]; c++) {
@@ -262,7 +331,10 @@ cache_flush(int force)
 		sprintf(path, "/proc/net/rpc/%s/flush", cachelist[c]);
 		fd = open(path, O_RDWR);
 		if (fd >= 0) {
-			write(fd, stime, strlen(stime));
+			if (write(fd, stime, strlen(stime)) != strlen(stime)) {
+				xlog_warn("Writing to '%s' failed: errno %d (%s)",
+				path, errno, strerror(errno));
+			}
 			close(fd);
 		}
 	}