[Libguestfs] [PATCH] lib: Add optional 'append' parameter to copy-(device|file)-to-file APIs.
Richard W.M. Jones
rjones at redhat.com
Tue Jun 23 12:25:28 UTC 2015
This allows you to append one file to another:
copy-file-to-file /input.txt /output.txt append:true
will append the contents of /input.txt to /output.txt.
---
daemon/copy.c | 38 +++++++++++++++++++++++++++++++-------
generator/actions.ml | 29 +++++++++++++++++++++--------
2 files changed, 52 insertions(+), 15 deletions(-)
diff --git a/daemon/copy.c b/daemon/copy.c
index bab00fe..6f3e844 100644
--- a/daemon/copy.c
+++ b/daemon/copy.c
@@ -30,7 +30,6 @@
#include "actions.h"
/* wrflags */
-#define DEST_FILE_FLAGS O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY|O_CLOEXEC, 0666
#define DEST_DEVICE_FLAGS O_WRONLY|O_CLOEXEC, 0
/* flags */
@@ -210,8 +209,13 @@ copy (const char *src, const char *src_display,
int
do_copy_device_to_device (const char *src, const char *dest,
int64_t srcoffset, int64_t destoffset, int64_t size,
- int sparse)
+ int sparse, int append)
{
+ if ((optargs_bitmask & GUESTFS_COPY_DEVICE_TO_DEVICE_APPEND_BITMASK) &&
+ append) {
+ reply_with_error ("the append flag cannot be set for this call");
+ return -1;
+ }
return copy (src, src, dest, dest, DEST_DEVICE_FLAGS, 0,
srcoffset, destoffset, size, sparse);
}
@@ -219,23 +223,30 @@ do_copy_device_to_device (const char *src, const char *dest,
int
do_copy_device_to_file (const char *src, const char *dest,
int64_t srcoffset, int64_t destoffset, int64_t size,
- int sparse)
+ int sparse, int append)
{
CLEANUP_FREE char *dest_buf = sysroot_path (dest);
+ int wrflags = O_WRONLY|O_CREAT|O_NOCTTY|O_CLOEXEC;
if (!dest_buf) {
reply_with_perror ("malloc");
return -1;
}
- return copy (src, src, dest_buf, dest, DEST_FILE_FLAGS, 0,
+ if ((optargs_bitmask & GUESTFS_COPY_DEVICE_TO_FILE_APPEND_BITMASK) &&
+ append)
+ wrflags |= O_APPEND;
+ else
+ wrflags |= O_TRUNC;
+
+ return copy (src, src, dest_buf, dest, wrflags, 0666, 0,
srcoffset, destoffset, size, sparse);
}
int
do_copy_file_to_device (const char *src, const char *dest,
int64_t srcoffset, int64_t destoffset, int64_t size,
- int sparse)
+ int sparse, int append)
{
CLEANUP_FREE char *src_buf = sysroot_path (src);
@@ -244,6 +255,12 @@ do_copy_file_to_device (const char *src, const char *dest,
return -1;
}
+ if ((optargs_bitmask & GUESTFS_COPY_FILE_TO_DEVICE_APPEND_BITMASK) &&
+ append) {
+ reply_with_error ("the append flag cannot be set for this call");
+ return -1;
+ }
+
return copy (src_buf, src, dest, dest, DEST_DEVICE_FLAGS, 0,
srcoffset, destoffset, size, sparse);
}
@@ -251,9 +268,10 @@ do_copy_file_to_device (const char *src, const char *dest,
int
do_copy_file_to_file (const char *src, const char *dest,
int64_t srcoffset, int64_t destoffset, int64_t size,
- int sparse)
+ int sparse, int append)
{
CLEANUP_FREE char *src_buf = NULL, *dest_buf = NULL;
+ int wrflags = O_WRONLY|O_CREAT|O_NOCTTY|O_CLOEXEC;
src_buf = sysroot_path (src);
if (!src_buf) {
@@ -267,7 +285,13 @@ do_copy_file_to_file (const char *src, const char *dest,
return -1;
}
- return copy (src_buf, src, dest_buf, dest, DEST_FILE_FLAGS,
+ if ((optargs_bitmask & GUESTFS_COPY_FILE_TO_FILE_APPEND_BITMASK) &&
+ append)
+ wrflags |= O_APPEND;
+ else
+ wrflags |= O_TRUNC;
+
+ return copy (src_buf, src, dest_buf, dest, wrflags, 0666,
COPY_UNLINK_DEST_ON_FAILURE,
srcoffset, destoffset, size, sparse);
}
diff --git a/generator/actions.ml b/generator/actions.ml
index d5e5ccf..11b8652 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -9424,7 +9424,7 @@ See also C<guestfs_part_to_dev>." };
{ defaults with
name = "copy_device_to_device"; added = (1, 13, 25);
- style = RErr, [Device "src"; Device "dest"], [OInt64 "srcoffset"; OInt64 "destoffset"; OInt64 "size"; OBool "sparse"];
+ style = RErr, [Device "src"; Device "dest"], [OInt64 "srcoffset"; OInt64 "destoffset"; OInt64 "size"; OBool "sparse"; OBool "append"];
proc_nr = Some 294;
progress = true;
shortdesc = "copy from source device to destination device";
@@ -9448,6 +9448,11 @@ overlapping regions may not be copied correctly.
If the destination is a file, it is created if required. If
the destination file is not large enough, it is extended.
+If the destination is a file and the C<append> flag is not set,
+then the destination file is truncated. If the C<append> flag is
+set, then the copy appends to the destination file. The C<append>
+flag currently cannot be set for devices.
+
If the C<sparse> flag is true then the call avoids writing
blocks that contain only zeroes, which can help in some situations
where the backing disk is thin-provisioned. Note that unless
@@ -9456,7 +9461,7 @@ in incorrect copying." };
{ defaults with
name = "copy_device_to_file"; added = (1, 13, 25);
- style = RErr, [Device "src"; Pathname "dest"], [OInt64 "srcoffset"; OInt64 "destoffset"; OInt64 "size"; OBool "sparse"];
+ style = RErr, [Device "src"; Pathname "dest"], [OInt64 "srcoffset"; OInt64 "destoffset"; OInt64 "size"; OBool "sparse"; OBool "append"];
proc_nr = Some 295;
progress = true;
shortdesc = "copy from source device to destination file";
@@ -9466,7 +9471,7 @@ of this call." };
{ defaults with
name = "copy_file_to_device"; added = (1, 13, 25);
- style = RErr, [Pathname "src"; Device "dest"], [OInt64 "srcoffset"; OInt64 "destoffset"; OInt64 "size"; OBool "sparse"];
+ style = RErr, [Pathname "src"; Device "dest"], [OInt64 "srcoffset"; OInt64 "destoffset"; OInt64 "size"; OBool "sparse"; OBool "append"];
proc_nr = Some 296;
progress = true;
shortdesc = "copy from source file to destination device";
@@ -9476,24 +9481,32 @@ of this call." };
{ defaults with
name = "copy_file_to_file"; added = (1, 13, 25);
- style = RErr, [Pathname "src"; Pathname "dest"], [OInt64 "srcoffset"; OInt64 "destoffset"; OInt64 "size"; OBool "sparse"];
+ style = RErr, [Pathname "src"; Pathname "dest"], [OInt64 "srcoffset"; OInt64 "destoffset"; OInt64 "size"; OBool "sparse"; OBool "append"];
proc_nr = Some 297;
progress = true;
tests = [
InitScratchFS, Always, TestResult (
[["mkdir"; "/copyff"];
["write"; "/copyff/src"; "hello, world"];
- ["copy_file_to_file"; "/copyff/src"; "/copyff/dest"; ""; ""; ""; ""];
+ ["copy_file_to_file"; "/copyff/src"; "/copyff/dest"; ""; ""; ""; ""; "false"];
["read_file"; "/copyff/dest"]],
"compare_buffers (ret, size, \"hello, world\", 12) == 0"), [];
- let size = 1024 * 1024 in
InitScratchFS, Always, TestResultTrue (
+ let size = 1024 * 1024 in
[["mkdir"; "/copyff2"];
["fill"; "0"; string_of_int size; "/copyff2/src"];
["touch"; "/copyff2/dest"];
["truncate_size"; "/copyff2/dest"; string_of_int size];
- ["copy_file_to_file"; "/copyff2/src"; "/copyff2/dest"; ""; ""; ""; "true"];
- ["is_zero"; "/copyff2/dest"]]), []
+ ["copy_file_to_file"; "/copyff2/src"; "/copyff2/dest"; ""; ""; ""; "true"; "false"];
+ ["is_zero"; "/copyff2/dest"]]), [];
+ InitScratchFS, Always, TestResult (
+ [["mkdir"; "/copyff3"];
+ ["write"; "/copyff3/src"; "hello, world"];
+ ["copy_file_to_file"; "/copyff3/src"; "/copyff3/dest"; ""; ""; ""; ""; "true"];
+ ["copy_file_to_file"; "/copyff3/src"; "/copyff3/dest"; ""; ""; ""; ""; "true"];
+ ["copy_file_to_file"; "/copyff3/src"; "/copyff3/dest"; ""; ""; ""; ""; "true"];
+ ["read_file"; "/copyff3/dest"]],
+ "compare_buffers (ret, size, \"hello, worldhello, worldhello, world\", 12*3) == 0"), [];
];
shortdesc = "copy from source file to destination file";
longdesc = "\
--
2.3.1
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