diff options
| author | Hannes Reinecke | 2014-03-20 11:03:49 +0100 |
|---|---|---|
| committer | Karel Zak | 2014-03-20 13:43:40 +0100 |
| commit | 296d96e20e565e497e9510e6ac9b71e0a0ca447d (patch) | |
| tree | 02857de3a8255909f175f7c48ef3738084b71c94 /libblkid/src/probe.c | |
| parent | include/closestream: don't wipe errno on EPIPE (diff) | |
| download | kernel-qcow2-util-linux-296d96e20e565e497e9510e6ac9b71e0a0ca447d.tar.gz kernel-qcow2-util-linux-296d96e20e565e497e9510e6ac9b71e0a0ca447d.tar.xz kernel-qcow2-util-linux-296d96e20e565e497e9510e6ac9b71e0a0ca447d.zip | |
blkid: stop scanning on I/O error
Whenever we fail to read from a device it's pointless to
continue with probing; we should be failing immediately.
Otherwise the system will continue logging I/O errors.
This patch updates the probe functions to return the
negative error number on error and BLKID_PROBE_NONE
if not found.
[kzak@redhat.com: - fix s/return errno/return -errno/]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
Diffstat (limited to 'libblkid/src/probe.c')
| -rw-r--r-- | libblkid/src/probe.c | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c index e20c61bb1..526ca6088 100644 --- a/libblkid/src/probe.c +++ b/libblkid/src/probe.c @@ -569,13 +569,17 @@ unsigned char *blkid_probe_get_buffer(blkid_probe pr, if (!bf) { ssize_t ret; - if (blkid_llseek(pr->fd, pr->off + off, SEEK_SET) < 0) + if (blkid_llseek(pr->fd, pr->off + off, SEEK_SET) < 0) { + errno = 0; return NULL; + } /* allocate info and space for data by why call */ bf = calloc(1, sizeof(struct blkid_bufinfo) + len); - if (!bf) + if (!bf) { + errno = ENOMEM; return NULL; + } bf->data = ((unsigned char *) bf) + sizeof(struct blkid_bufinfo); bf->len = len; @@ -587,7 +591,10 @@ unsigned char *blkid_probe_get_buffer(blkid_probe pr, ret = read(pr->fd, bf->data, len); if (ret != (ssize_t) len) { + DBG(LOWPROBE, blkid_debug("\tbuffer read: return %zd error %m", ret)); free(bf); + if (ret >= 0) + errno = 0; return NULL; } list_add_tail(&bf->bufs, &pr->buffers); @@ -776,6 +783,17 @@ int blkid_probe_set_dimension(blkid_probe pr, return 0; } +/** + * blkid_probe_get_idmag: + * @pr: probe + * @id: id information + * @offset: begin of probing area + * @res: found id information + * + * Check for matching magic value. + * Returns BLKID_PROBE_OK if found, BLKID_PROBE_NONE if not found + * or no magic present, or negative value on error. + */ int blkid_probe_get_idmag(blkid_probe pr, const struct blkid_idinfo *id, blkid_loff_t *offset, const struct blkid_idmag **res) { @@ -794,6 +812,8 @@ int blkid_probe_get_idmag(blkid_probe pr, const struct blkid_idinfo *id, off = (mag->kboff + (mag->sboff >> 10)) << 10; buf = blkid_probe_get_buffer(pr, off, 1024); + if (!buf && errno) + return -errno; if (buf && !memcmp(mag->magic, buf + (mag->sboff & 0x3ff), mag->len)) { DBG(LOWPROBE, blkid_debug("\tmagic sboff=%u, kboff=%ld", @@ -802,16 +822,16 @@ int blkid_probe_get_idmag(blkid_probe pr, const struct blkid_idinfo *id, *offset = off + (mag->sboff & 0x3ff); if (res) *res = mag; - return 0; + return BLKID_PROBE_OK; } mag++; } if (id && id->magics[0].magic) /* magic string(s) defined, but not found */ - return 1; + return BLKID_PROBE_NONE; - return 0; + return BLKID_PROBE_OK; } static inline void blkid_probe_start(blkid_probe pr) |