Re: AW: [PATCH v2 4/9] loop:refactor: extract subfunction set_loop_info()
On 2022/11/18 20:27, Walter Harms wrote:
on other minor
if (rc && errno == ENXIO)
turn it on its head safes one indent level
if ( !rc || errno != ENXIO )
return -1; // failed to get loopinfo
jm2c
Here's for copy-paste consistency
Simplification has been implemented in patch 5 by extracting functions
Von: busybox im Auftrag von Xiaoming Ni
Gesendet: Freitag, 18. November 2022 13:14:43
An: busybox@busybox.net; vda.li...@googlemail.com; c...@gmx.com;
explore...@gmail.com
Cc: wang...@huawei.com
Betreff: [PATCH v2 4/9] loop:refactor: extract subfunction set_loop_info()
Step 4 of micro-refactoring the set_loop():
Extract subfunction set_loop_info() from set_loop()
function old new delta
set_loop 734 700 -34
--
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-34) Total: -34 bytes
Signed-off-by: Xiaoming Ni
---
libbb/loop.c | 91 +++-
1 file changed, 47 insertions(+), 44 deletions(-)
diff --git a/libbb/loop.c b/libbb/loop.c
index 91c3a45c4..89adc4f94 100644
--- a/libbb/loop.c
+++ b/libbb/loop.c
@@ -126,6 +126,47 @@ static int open_file(const char *file, unsigned flags, int
*mode)
return ffd;
}
+static int set_loop_info(int ffd, int lfd, const char *file,
+ unsigned long long offset, unsigned long long sizelimit,
unsigned flags)
+{
+ int rc;
+ bb_loop_info loopinfo;
+
+ rc = ioctl(lfd, BB_LOOP_GET_STATUS, );
+
+ /* If device is free, try to claim it */
+ if (rc && errno == ENXIO) {
+ /* Associate free loop device with file */
+ if (ioctl(lfd, LOOP_SET_FD, ffd)) {
+ return -1;
+ }
+ memset(, 0, sizeof(loopinfo));
+ safe_strncpy((char *)loopinfo.lo_file_name, file, LO_NAME_SIZE);
+ loopinfo.lo_offset = offset;
+ loopinfo.lo_sizelimit = sizelimit;
+ /*
+* Used by mount to set LO_FLAGS_AUTOCLEAR.
+* LO_FLAGS_READ_ONLY is not set because RO is controlled by
open type of the file.
+* Note that closing LO_FLAGS_AUTOCLEARed lfd before mount
+* is wrong (would free the loop device!)
+*/
+ loopinfo.lo_flags = (flags & ~BB_LO_FLAGS_READ_ONLY);
+ rc = ioctl(lfd, BB_LOOP_SET_STATUS, );
+ if (rc != 0 && (loopinfo.lo_flags & BB_LO_FLAGS_AUTOCLEAR)) {
+ /* Old kernel, does not support LO_FLAGS_AUTOCLEAR? */
+ /* (this code path is not tested) */
+ loopinfo.lo_flags -= BB_LO_FLAGS_AUTOCLEAR;
+ rc = ioctl(lfd, BB_LOOP_SET_STATUS, );
+ }
+ if (rc == 0) {
+ return lfd;
+ }
+ /* failure, undo LOOP_SET_FD */
+ ioctl(lfd, LOOP_CLR_FD, 0); // actually, 0 param is unnecessary
+ }
+ return -1;
+}
+
/* Returns opened fd to the loop device, <0 on error.
* *device is loop device to use, or if *device==NULL finds a loop device to
* mount it on and sets *device to a strdup of that loop device name.
@@ -135,7 +176,6 @@ int FAST_FUNC set_loop(char **device, const char *file,
unsigned long long offse
{
char dev[LOOP_NAMESIZE];
char *try;
- bb_loop_info loopinfo;
struct stat statbuf;
int i, lfd, ffd, mode, rc;
@@ -190,49 +230,12 @@ int FAST_FUNC set_loop(char **device, const char *file,
unsigned long long offse
}
goto try_next_loopN;
}
-
- rc = ioctl(lfd, BB_LOOP_GET_STATUS, );
-
- /* If device is free, try to claim it */
- if (rc && errno == ENXIO) {
- /* Associate free loop device with file */
- if (ioctl(lfd, LOOP_SET_FD, ffd)) {
- close(lfd);
- /* Ouch. Are we racing with other mount? */
- if (!*device) {
-//TODO: add "if (--failcount != 0) ..."?
- continue;
- } else {
- break;
- }
- }
- memset(, 0, sizeof(loopinfo));
- safe_strncpy((char *)loopinfo.lo_file_name, file,
LO_NAME_SIZE);
- loopinfo.lo_offset = offset;
- loopinfo.lo_sizelimit = sizelimit;
- /*
-* Used by mount to set LO_FLAGS_AUTOCLEAR.
-
AW: [PATCH v2 4/9] loop:refactor: extract subfunction set_loop_info()
on other minor
if (rc && errno == ENXIO)
turn it on its head safes one indent level
if ( !rc || errno != ENXIO )
return -1; // failed to get loopinfo
jm2c
Von: busybox im Auftrag von Xiaoming Ni
Gesendet: Freitag, 18. November 2022 13:14:43
An: busybox@busybox.net; vda.li...@googlemail.com; c...@gmx.com;
explore...@gmail.com
Cc: wang...@huawei.com
Betreff: [PATCH v2 4/9] loop:refactor: extract subfunction set_loop_info()
Step 4 of micro-refactoring the set_loop():
Extract subfunction set_loop_info() from set_loop()
function old new delta
set_loop 734 700 -34
--
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-34) Total: -34 bytes
Signed-off-by: Xiaoming Ni
---
libbb/loop.c | 91 +++-
1 file changed, 47 insertions(+), 44 deletions(-)
diff --git a/libbb/loop.c b/libbb/loop.c
index 91c3a45c4..89adc4f94 100644
--- a/libbb/loop.c
+++ b/libbb/loop.c
@@ -126,6 +126,47 @@ static int open_file(const char *file, unsigned flags, int
*mode)
return ffd;
}
+static int set_loop_info(int ffd, int lfd, const char *file,
+ unsigned long long offset, unsigned long long sizelimit,
unsigned flags)
+{
+ int rc;
+ bb_loop_info loopinfo;
+
+ rc = ioctl(lfd, BB_LOOP_GET_STATUS, );
+
+ /* If device is free, try to claim it */
+ if (rc && errno == ENXIO) {
+ /* Associate free loop device with file */
+ if (ioctl(lfd, LOOP_SET_FD, ffd)) {
+ return -1;
+ }
+ memset(, 0, sizeof(loopinfo));
+ safe_strncpy((char *)loopinfo.lo_file_name, file, LO_NAME_SIZE);
+ loopinfo.lo_offset = offset;
+ loopinfo.lo_sizelimit = sizelimit;
+ /*
+* Used by mount to set LO_FLAGS_AUTOCLEAR.
+* LO_FLAGS_READ_ONLY is not set because RO is controlled by
open type of the file.
+* Note that closing LO_FLAGS_AUTOCLEARed lfd before mount
+* is wrong (would free the loop device!)
+*/
+ loopinfo.lo_flags = (flags & ~BB_LO_FLAGS_READ_ONLY);
+ rc = ioctl(lfd, BB_LOOP_SET_STATUS, );
+ if (rc != 0 && (loopinfo.lo_flags & BB_LO_FLAGS_AUTOCLEAR)) {
+ /* Old kernel, does not support LO_FLAGS_AUTOCLEAR? */
+ /* (this code path is not tested) */
+ loopinfo.lo_flags -= BB_LO_FLAGS_AUTOCLEAR;
+ rc = ioctl(lfd, BB_LOOP_SET_STATUS, );
+ }
+ if (rc == 0) {
+ return lfd;
+ }
+ /* failure, undo LOOP_SET_FD */
+ ioctl(lfd, LOOP_CLR_FD, 0); // actually, 0 param is unnecessary
+ }
+ return -1;
+}
+
/* Returns opened fd to the loop device, <0 on error.
* *device is loop device to use, or if *device==NULL finds a loop device to
* mount it on and sets *device to a strdup of that loop device name.
@@ -135,7 +176,6 @@ int FAST_FUNC set_loop(char **device, const char *file,
unsigned long long offse
{
char dev[LOOP_NAMESIZE];
char *try;
- bb_loop_info loopinfo;
struct stat statbuf;
int i, lfd, ffd, mode, rc;
@@ -190,49 +230,12 @@ int FAST_FUNC set_loop(char **device, const char *file,
unsigned long long offse
}
goto try_next_loopN;
}
-
- rc = ioctl(lfd, BB_LOOP_GET_STATUS, );
-
- /* If device is free, try to claim it */
- if (rc && errno == ENXIO) {
- /* Associate free loop device with file */
- if (ioctl(lfd, LOOP_SET_FD, ffd)) {
- close(lfd);
- /* Ouch. Are we racing with other mount? */
- if (!*device) {
-//TODO: add "if (--failcount != 0) ..."?
- continue;
- } else {
- break;
- }
- }
- memset(, 0, sizeof(loopinfo));
- safe_strncpy((char *)loopinfo.lo_file_name, file,
LO_NAME_SIZE);
- loopinfo.lo_offset = offset;
- loopinfo.lo_sizelimit = sizelimit;
- /*
-* Used by mount to set LO_FLAGS_AUTOCLEAR.
-* LO_FLAGS_READ_ONLY is not set because RO is
controlled by open type of the file.
-* Note that closing LO_FLAGS_AUTOCLEARed
[PATCH v2 4/9] loop:refactor: extract subfunction set_loop_info()
Step 4 of micro-refactoring the set_loop():
Extract subfunction set_loop_info() from set_loop()
function old new delta
set_loop 734 700 -34
--
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-34) Total: -34 bytes
Signed-off-by: Xiaoming Ni
---
libbb/loop.c | 91 +++-
1 file changed, 47 insertions(+), 44 deletions(-)
diff --git a/libbb/loop.c b/libbb/loop.c
index 91c3a45c4..89adc4f94 100644
--- a/libbb/loop.c
+++ b/libbb/loop.c
@@ -126,6 +126,47 @@ static int open_file(const char *file, unsigned flags, int
*mode)
return ffd;
}
+static int set_loop_info(int ffd, int lfd, const char *file,
+ unsigned long long offset, unsigned long long sizelimit,
unsigned flags)
+{
+ int rc;
+ bb_loop_info loopinfo;
+
+ rc = ioctl(lfd, BB_LOOP_GET_STATUS, );
+
+ /* If device is free, try to claim it */
+ if (rc && errno == ENXIO) {
+ /* Associate free loop device with file */
+ if (ioctl(lfd, LOOP_SET_FD, ffd)) {
+ return -1;
+ }
+ memset(, 0, sizeof(loopinfo));
+ safe_strncpy((char *)loopinfo.lo_file_name, file, LO_NAME_SIZE);
+ loopinfo.lo_offset = offset;
+ loopinfo.lo_sizelimit = sizelimit;
+ /*
+* Used by mount to set LO_FLAGS_AUTOCLEAR.
+* LO_FLAGS_READ_ONLY is not set because RO is controlled by
open type of the file.
+* Note that closing LO_FLAGS_AUTOCLEARed lfd before mount
+* is wrong (would free the loop device!)
+*/
+ loopinfo.lo_flags = (flags & ~BB_LO_FLAGS_READ_ONLY);
+ rc = ioctl(lfd, BB_LOOP_SET_STATUS, );
+ if (rc != 0 && (loopinfo.lo_flags & BB_LO_FLAGS_AUTOCLEAR)) {
+ /* Old kernel, does not support LO_FLAGS_AUTOCLEAR? */
+ /* (this code path is not tested) */
+ loopinfo.lo_flags -= BB_LO_FLAGS_AUTOCLEAR;
+ rc = ioctl(lfd, BB_LOOP_SET_STATUS, );
+ }
+ if (rc == 0) {
+ return lfd;
+ }
+ /* failure, undo LOOP_SET_FD */
+ ioctl(lfd, LOOP_CLR_FD, 0); // actually, 0 param is unnecessary
+ }
+ return -1;
+}
+
/* Returns opened fd to the loop device, <0 on error.
* *device is loop device to use, or if *device==NULL finds a loop device to
* mount it on and sets *device to a strdup of that loop device name.
@@ -135,7 +176,6 @@ int FAST_FUNC set_loop(char **device, const char *file,
unsigned long long offse
{
char dev[LOOP_NAMESIZE];
char *try;
- bb_loop_info loopinfo;
struct stat statbuf;
int i, lfd, ffd, mode, rc;
@@ -190,49 +230,12 @@ int FAST_FUNC set_loop(char **device, const char *file,
unsigned long long offse
}
goto try_next_loopN;
}
-
- rc = ioctl(lfd, BB_LOOP_GET_STATUS, );
-
- /* If device is free, try to claim it */
- if (rc && errno == ENXIO) {
- /* Associate free loop device with file */
- if (ioctl(lfd, LOOP_SET_FD, ffd)) {
- close(lfd);
- /* Ouch. Are we racing with other mount? */
- if (!*device) {
-//TODO: add "if (--failcount != 0) ..."?
- continue;
- } else {
- break;
- }
- }
- memset(, 0, sizeof(loopinfo));
- safe_strncpy((char *)loopinfo.lo_file_name, file,
LO_NAME_SIZE);
- loopinfo.lo_offset = offset;
- loopinfo.lo_sizelimit = sizelimit;
- /*
-* Used by mount to set LO_FLAGS_AUTOCLEAR.
-* LO_FLAGS_READ_ONLY is not set because RO is
controlled by open type of the file.
-* Note that closing LO_FLAGS_AUTOCLEARed lfd before
mount
-* is wrong (would free the loop device!)
-*/
- loopinfo.lo_flags = (flags & ~BB_LO_FLAGS_READ_ONLY);
- rc = ioctl(lfd, BB_LOOP_SET_STATUS, );
- if (rc != 0 && (loopinfo.lo_flags &
BB_LO_FLAGS_AUTOCLEAR)) {
- /* Old kernel, does not support
LO_FLAGS_AUTOCLEAR? */
- /* (this code path is not tested) */
-
