From: Chunyan Liu <cyliu@suse.com>
To: xen-devel@lists.xen.org
Cc: george.dunlap@eu.citrix.com, wei.liu2@citrix.com,
Ian.Jackson@eu.citrix.com, ian.campbell@citrix.com,
Chunyan Liu <cyliu@suse.com>
Subject: [PATCH V4 2/7] libxl_read_file_contents: add new entry to read sysfs file
Date: Wed, 10 Jun 2015 11:20:36 +0800 [thread overview]
Message-ID: <1433906441-3280-3-git-send-email-cyliu@suse.com> (raw)
In-Reply-To: <1433906441-3280-1-git-send-email-cyliu@suse.com>
Sysfs file has size=4096 but actual file content is less than that.
Current libxl_read_file_contents will treat it as error when file size
and actual file content differs, so reading sysfs file content with
this function always fails.
Add a new entry libxl_read_sysfs_file_contents to handle sysfs file
specially. It would be used in later pvusb work.
Signed-off-by: Chunyan Liu <cyliu@suse.com>
---
Changes:
- instead of hacking lixbl_read_file_contents for sysfs file, add
a new entry libxl_read_sysfs_file_contents to do the work.
tools/libxl/libxl_utils.c | 24 ++++++++++++++++++++----
tools/libxl/libxl_utils.h | 2 ++
2 files changed, 22 insertions(+), 4 deletions(-)
diff --git a/tools/libxl/libxl_utils.c b/tools/libxl/libxl_utils.c
index f6be2d7..d0d56c2 100644
--- a/tools/libxl/libxl_utils.c
+++ b/tools/libxl/libxl_utils.c
@@ -322,8 +322,10 @@ out:
return rc;
}
-int libxl_read_file_contents(libxl_ctx *ctx, const char *filename,
- void **data_r, int *datalen_r) {
+static int libxl_read_file_contents_core(libxl_ctx *ctx, const char *filename,
+ void **data_r, int *datalen_r,
+ bool is_sysfs_file)
+{
GC_INIT(ctx);
FILE *f = 0;
uint8_t *data = 0;
@@ -360,15 +362,16 @@ int libxl_read_file_contents(libxl_ctx *ctx, const char *filename,
if (stab.st_size && data_r) {
data = malloc(datalen);
+ memset(data, 0, datalen);
if (!data) goto xe;
rs = fread(data, 1, datalen, f);
- if (rs != datalen) {
+ if (rs != datalen && !(feof(f) && is_sysfs_file)) {
if (ferror(f))
LOGE(ERROR, "failed to read %s", filename);
else if (feof(f))
LOG(ERROR, "%s changed size while we were reading it",
- filename);
+ filename);
else
abort();
goto xe;
@@ -396,6 +399,19 @@ int libxl_read_file_contents(libxl_ctx *ctx, const char *filename,
return e;
}
+int libxl_read_file_contents(libxl_ctx *ctx, const char *filename,
+ void **data_r, int *datalen_r)
+{
+ return libxl_read_file_contents_core(ctx, filename, data_r, datalen_r, 0);
+}
+
+int libxl_read_sysfs_file_contents(libxl_ctx *ctx, const char *filename,
+ void **data_r, int *datalen_r)
+{
+ return libxl_read_file_contents_core(ctx, filename, data_r, datalen_r, 1);
+}
+
+
#define READ_WRITE_EXACTLY(rw, zero_is_eof, constdata) \
\
int libxl_##rw##_exactly(libxl_ctx *ctx, int fd, \
diff --git a/tools/libxl/libxl_utils.h b/tools/libxl/libxl_utils.h
index 1c1761d..7639662 100644
--- a/tools/libxl/libxl_utils.h
+++ b/tools/libxl/libxl_utils.h
@@ -38,6 +38,8 @@ int libxl_is_stubdom(libxl_ctx *ctx, uint32_t domid, uint32_t *target_domid);
int libxl_create_logfile(libxl_ctx *ctx, const char *name, char **full_name);
int libxl_string_to_backend(libxl_ctx *ctx, char *s, libxl_disk_backend *backend);
+int libxl_read_sysfs_file_contents(libxl_ctx *ctx, const char *filename,
+ void **data_r, int *datalen_r);
int libxl_read_file_contents(libxl_ctx *ctx, const char *filename,
void **data_r, int *datalen_r);
/* Reads the contents of the plain file filename into a mallocd
--
2.1.4
next prev parent reply other threads:[~2015-06-10 3:20 UTC|newest]
Thread overview: 88+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-10 3:20 [PATCH V4 0/7] xen pvusb toolstack work Chunyan Liu
2015-06-10 3:20 ` [PATCH V4 1/7] libxl: export some functions for pvusb use Chunyan Liu
2015-06-11 16:08 ` Ian Jackson
2015-06-11 16:28 ` Wei Liu
2015-06-12 15:14 ` Ian Jackson
2015-06-10 3:20 ` Chunyan Liu [this message]
2015-06-11 16:16 ` [PATCH V4 2/7] libxl_read_file_contents: add new entry to read sysfs file Ian Jackson
2015-06-12 7:00 ` Chun Yan Liu
2015-06-12 15:11 ` Ian Jackson
2015-06-10 3:20 ` [PATCH V4 3/7] libxl: add pvusb API Chunyan Liu
2015-06-11 15:00 ` Juergen Gross
2015-06-11 16:07 ` Ian Jackson
2015-06-11 16:42 ` Ian Jackson
2015-06-12 7:39 ` Chun Yan Liu
2015-06-12 8:06 ` Chun Yan Liu
2015-06-12 11:22 ` Ian Jackson
2015-06-15 14:17 ` George Dunlap
2015-06-15 14:25 ` Jürgen Groß
2015-06-15 14:34 ` George Dunlap
2015-06-15 18:26 ` Juergen Gross
2015-06-16 10:30 ` George Dunlap
2015-06-16 10:51 ` Juergen Gross
2015-06-16 11:11 ` George Dunlap
2015-06-16 11:19 ` Juergen Gross
2015-06-16 11:23 ` George Dunlap
2015-06-16 11:44 ` Ian Jackson
2015-06-17 11:24 ` Ian Campbell
2015-06-18 11:50 ` George Dunlap
2015-06-18 12:08 ` George Dunlap
2015-06-18 13:03 ` Juergen Gross
2015-06-22 13:29 ` Proposed plan for libxl USB interface (was Re: [PATCH V4 3/7] libxl: add pvusb API) George Dunlap
2015-06-22 14:14 ` Juergen Gross
2015-06-22 14:22 ` Ian Jackson
2015-06-23 2:42 ` Chun Yan Liu
2015-06-23 2:43 ` Chun Yan Liu
2015-06-23 2:44 ` Chun Yan Liu
2015-06-16 10:41 ` [PATCH V4 3/7] libxl: add pvusb API Ian Jackson
2015-06-16 10:56 ` Jürgen Groß
2015-06-16 11:03 ` George Dunlap
2015-06-16 11:10 ` Ian Jackson
2015-06-16 11:25 ` Juergen Gross
2015-06-16 11:45 ` George Dunlap
2015-06-16 12:02 ` Ian Jackson
2015-06-16 13:19 ` George Dunlap
2015-06-16 13:32 ` Juergen Gross
2015-06-16 13:37 ` [PATCH V4 3/7] libxl: add pvusb API [and 1 more messages] Ian Jackson
2015-06-16 14:41 ` George Dunlap
2015-06-16 15:58 ` Sander Eikelenboom
2015-06-16 15:59 ` Ian Jackson
2015-06-16 16:34 ` George Dunlap
2015-06-17 3:59 ` Juergen Gross
2015-06-17 10:27 ` George Dunlap
2015-06-18 6:24 ` Chun Yan Liu
2015-06-16 11:45 ` [PATCH V4 3/7] libxl: add pvusb API Ian Jackson
2015-06-16 13:06 ` Juergen Gross
2015-06-16 13:09 ` George Dunlap
2015-06-16 13:23 ` Juergen Gross
2015-06-16 13:29 ` George Dunlap
2015-06-16 13:49 ` Juergen Gross
2015-06-16 14:06 ` George Dunlap
2015-06-16 14:20 ` Juergen Gross
2015-06-16 14:37 ` George Dunlap
2015-06-17 11:34 ` Ian Campbell
2015-06-17 11:40 ` Juergen Gross
2015-06-18 6:20 ` Chun Yan Liu
2015-06-18 7:02 ` Juergen Gross
2015-06-18 8:50 ` Ian Campbell
2015-06-18 13:02 ` Juergen Gross
2015-06-16 15:38 ` George Dunlap
2015-06-16 11:01 ` George Dunlap
2015-06-16 11:12 ` Ian Jackson
2015-06-16 11:21 ` George Dunlap
2015-06-16 16:32 ` Ian Jackson
2015-06-16 16:39 ` George Dunlap
2015-06-16 16:51 ` Ross Philipson
2015-06-17 4:03 ` Jürgen Groß
2015-06-17 13:48 ` Ross Philipson
2015-06-15 17:47 ` George Dunlap
2015-06-23 10:18 ` Chun Yan Liu
2015-06-23 11:29 ` George Dunlap
2015-06-24 2:26 ` Chun Yan Liu
2015-06-10 3:20 ` [PATCH V4 4/7] libxl: add libxl_device_usb_assignable_list API Chunyan Liu
2015-06-10 3:20 ` [PATCH V4 5/7] xl: add pvusb commands Chunyan Liu
2015-06-12 7:37 ` Juergen Gross
2015-06-12 8:03 ` Chun Yan Liu
2015-06-12 8:22 ` Juergen Gross
2015-06-10 3:20 ` [PATCH V4 6/7] xl: add usb-assignable-list command Chunyan Liu
2015-06-10 3:20 ` [PATCH V4 7/7] domcreate: support pvusb in configuration file Chunyan Liu
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