git » libjio » commit b0bed7b

diff --git a/Makefile b/Makefile
index a032e05..31942ad 100644
--- a/Makefile
+++ b/Makefile
@@ -3,7 +3,7 @@ include Make.conf
 
 
 # objects to build
-OBJS = common.o trans.o check.o unix.o ansi.o
+OBJS = checksum.o common.o trans.o check.o unix.o ansi.o
 
 # rules
 default: all
diff --git a/check.c b/check.c
index ba7cd4c..a6ff36a 100644
--- a/check.c
+++ b/check.c
@@ -95,13 +95,14 @@ int jfsck(const char *name, struct jfsck_result *res)
 {
 	int fd, tfd, rv, i;
 	unsigned int maxtid;
+	uint32_t csum1, csum2;
 	char jdir[PATH_MAX], jlockfile[PATH_MAX], tname[PATH_MAX];
 	struct stat sinfo;
 	struct jfs fs;
 	struct jtrans *curts;
 	DIR *dir;
 	struct dirent *dent;
-	void *map;
+	unsigned char *map;
 	off_t filelen;
 
 
@@ -192,12 +193,20 @@ int jfsck(const char *name, struct jfsck_result *res)
 
 		filelen = lseek(tfd, 0, SEEK_END);
 		map = mmap(0, filelen, PROT_READ, MAP_SHARED, tfd, 0);
-		rv = fill_trans((unsigned char *) map, filelen, curts);
+		rv = fill_trans(map, filelen, curts);
 		if (rv != 1) {
 			res->broken++;
 			goto loop;
 		}
 
+		/* verify the checksum */
+		csum1 = checksum_map(map, filelen - (sizeof(uint32_t)));
+		csum2 = * (uint32_t *) (map + filelen - (sizeof(uint32_t)));
+		if (csum1 != csum2) {
+			res->corrupt++;
+			goto loop;
+		}
+
 		/* remove flags from the transaction */
 		curts->flags = 0;
 
diff --git a/checksum.c b/checksum.c
new file mode 100644
index 0000000..60e9758
--- /dev/null
+++ b/checksum.c
@@ -0,0 +1,47 @@
+
+/*
+ * libjio - A library for Journaled I/O
+ * Alberto Bertogli (albertogli@telpin.com.ar)
+ *
+ * Checksum functions
+ * Based on RFC 1071, "Computing the Internet Checksum"
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/mman.h>
+#include "common.h"
+
+
+int checksum(int fd, size_t len, uint32_t *csum)
+{
+	uint8_t *map;
+
+	map = (uint8_t *) mmap(NULL, len, PROT_READ, MAP_SHARED, fd, 0);
+	if (map == MAP_FAILED)
+		return 0;
+
+	*csum = checksum_map(map, len);
+
+	munmap(map, len);
+	return 1;
+}
+
+uint32_t checksum_map(uint8_t *map, size_t count)
+{
+	uint32_t sum = 0;
+
+	while( count > 1 )  {
+		sum += * (uint16_t *) map++;
+		count -= 2;
+	}
+
+	if( count > 0 )
+		sum += * (uint8_t *) map;
+
+	while (sum >> 16)
+		sum = (sum & 0xffff) + (sum >> 16);
+
+	return ~sum;
+}
+
diff --git a/common.h b/common.h
index 3e8f703..1b7bada 100644
--- a/common.h
+++ b/common.h
@@ -9,6 +9,10 @@
 #ifndef _COMMON_H
 #define _COMMON_H
 
+#include <sys/types.h>	/* for ssize_t and off_t */
+#include <stdint.h>	/* for uint*_t */
+
+
 #define _F_READ		0x00001
 #define _F_WRITE	0x00010
 #define _F_LOCK		0x00100
@@ -21,11 +25,15 @@
 #define F_TLOCKW	(_F_TLOCK | _F_WRITE)
 #define F_UNLOCK	(_F_ULOCK)
 
+
 off_t plockf(int fd, int cmd, off_t offset, off_t len);
 ssize_t spread(int fd, void *buf, size_t count, off_t offset);
 ssize_t spwrite(int fd, const void *buf, size_t count, off_t offset);
 int get_jdir(const char *filename, char *jdir);
 int get_jtfile(const char *filename, int tid, char *jtfile);
 
+int checksum(int fd, size_t len, uint32_t *csum);
+uint32_t checksum_map(uint8_t *map, size_t count);
+
 #endif
 
diff --git a/jiofsck.c b/jiofsck.c
index f9ac3ea..b7c8ad4 100644
--- a/jiofsck.c
+++ b/jiofsck.c
@@ -77,6 +77,7 @@ int main(int argc, char **argv)
 	printf("Broken head:\t %d\n", res.broken_head);
 	printf("Broken body:\t %d\n", res.broken_body);
 	printf("Load error:\t %d\n", res.load_error);
+	printf("Corrupt:\t %d\n", res.corrupt);
 	printf("Apply error:\t %d\n", res.apply_error);
 	printf("Reapplied:\t %d\n", res.reapplied);
 	printf("\n");
diff --git a/libjio.h b/libjio.h
index 90ef862..101a42e 100644
--- a/libjio.h
+++ b/libjio.h
@@ -67,6 +67,7 @@ struct jfsck_result {
 	int invalid;		/* invalid files in the journal directory */
 	int in_progress;	/* transactions in progress */
 	int broken;		/* transactions broken */
+	int corrupt;		/* corrupt transactions */
 	int apply_error;	/* errors applying the transaction */
 	int reapplied;		/* transactions that were reapplied */
 };
diff --git a/trans.c b/trans.c
index 3a25de2..6bc3904 100644
--- a/trans.c
+++ b/trans.c
@@ -179,6 +179,7 @@ int jtrans_add(struct jtrans *ts, const void *buf, size_t count, off_t offset)
 int jtrans_commit(struct jtrans *ts)
 {
 	int id, rv, fd = -1;
+	uint32_t csum;
 	char *name;
 	unsigned char *buf_init, *bufp;
 	struct joper *op;
@@ -307,6 +308,15 @@ int jtrans_commit(struct jtrans *ts)
 		curpos += op->len;
 	}
 
+	/* compute and save the checksum */
+	if (!checksum(fd, curpos, &csum))
+		goto exit;
+
+	rv = spwrite(fd, &csum, sizeof(uint32_t), curpos);
+	if (rv != sizeof(uint32_t))
+		goto exit;
+	curpos += sizeof(uint32_t);
+
 	/* this is a simple but efficient optimization: instead of doing
 	 * everything O_SYNC, we sync at this point only, this way we avoid
 	 * doing a lot of very small writes; in case of a crash the