empire/empserver
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Fix fillcache() and do_write() error handling

Browse source 
Fix test for interrupted I/O.  Catch read hitting EOF unexpectedly.
Log errors in more detail.
This commit is contained in:
Markus Armbruster 2008-03-21 09:13:04 +01:00
parent 54f1e9a07f
commit 570ce80edf
1 changed files with 23 additions and 14 deletions
Download patch file Download diff file Expand all files Collapse all files

37
src/lib/common/file.c
View file

@ -294,12 +294,12 @@ ef_read(int type, int id, void *into)
}
/*
* Fill cache of EP with elements starting at ID.
* Fill cache of file-backed EP with elements starting at ID.
* If any were read, return their number.
* Else return -1 and leave the cache unchanged.
*/
static int
fillcache(struct empfile *ep, int start)
fillcache(struct empfile *ep, int id)
{
int n, ret;
char *p;
@ -307,21 +307,27 @@ fillcache(struct empfile *ep, int start)
if (CANT_HAPPEN(ep->fd < 0 || !ep->cache))
return -1;
if (lseek(ep->fd, start * ep->size, SEEK_SET) == (off_t)-1) {
logerror("Error seeking %s (%s)", ep->file, strerror(errno));
if (lseek(ep->fd, id * ep->size, SEEK_SET) == (off_t)-1) {
logerror("Error seeking %s to elt %d (%s)",
ep->file, id, strerror(errno));
return -1;
}
p = ep->cache;
n = ep->csize * ep->size;
n = MIN(ep->csize, ep->fids - id) * ep->size;
while (n > 0) {
ret = read(ep->fd, p, n);
if (ret < 0) {
if (errno != EAGAIN) {
logerror("Error reading %s (%s)", ep->file, strerror(errno));
if (errno != EINTR) {
logerror("Error reading %s elt %d (%s)",
ep->file,
id + (int)((p - ep->cache) / ep->size),
strerror(errno));
break;
}
} else if (ret == 0) {
logerror("Unexpected EOF reading %s elt %d",
ep->file, id + (int)((p - ep->cache) / ep->size));
break;
} else {
p += ret;
@ -332,15 +338,15 @@ fillcache(struct empfile *ep, int start)
if (p == ep->cache)
return -1; /* nothing read, old cache still ok */
ep->baseid = start;
ep->baseid = id;
ep->cids = (p - ep->cache) / ep->size;
return ep->cids;
}
/*
* Write COUNT elements from BUF to EP, starting at ID.
* Write COUNT elements starting at ID from BUF to file-backed EP.
* Set the timestamp to NOW if the table has those.
* Return 0 on success, -1 on error.
* Return 0 on success, -1 on error (file may be corrupt then).
*/
static int
do_write(struct empfile *ep, void *buf, int id, int count, time_t now)
@ -369,7 +375,8 @@ do_write(struct empfile *ep, void *buf, int id, int count, time_t now)
}
if (lseek(ep->fd, id * ep->size, SEEK_SET) == (off_t)-1) {
logerror("Error seeking %s (%s)", ep->file, strerror(errno));
logerror("Error seeking %s to elt %d (%s)",
ep->file, id, strerror(errno));
return -1;
}
@ -378,9 +385,11 @@ do_write(struct empfile *ep, void *buf, int id, int count, time_t now)
while (n > 0) {
ret = write(ep->fd, p, n);
if (ret < 0) {
if (errno != EAGAIN) {
logerror("Error writing %s (%s)", ep->file, strerror(errno));
/* FIXME if this extended file, truncate back to old size */
if (errno != EINTR) {
logerror("Error writing %s elt %d (%s)",
ep->file,
id + (int)((p - (char *)buf) / ep->size),
strerror(errno));
return -1;
}
} else {