threads / patch / 37163

patchremote-testsvn: use internal argv_array of struct child_process in cmd_import()

Subject: [PATCH] remote-testsvn: use internal argv_array of struct child_process in cmd_import()

## tl;dr

6 messages between Jul 18, 2014 and Jul 18, 2014. Diffs are folded; open one to read it.

replies: 5people: 2as markdown or json

René Scharfe· Jul 18, 2014, 15:20 UTC · lore

Use the existing argv_array member instead of providing our own. This way we don't have to initialize or clean it up explicitly.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
---
 remote-testsvn.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

Show changes to remote-testsvn.c +4 −7

diff --git a/remote-testsvn.c b/remote-testsvn.c
index 6be55cb..31415bd 100644
--- a/remote-testsvn.c
+++ b/remote-testsvn.c
@@ -175,7 +175,6 @@ static int cmd_import(const char *line)
 	char *note_msg;
 	unsigned char head_sha1[20];
 	unsigned int startrev;
-	struct argv_array svndump_argv = ARGV_ARRAY_INIT;
 	struct child_process svndump_proc;
 
 	if (read_ref(private_ref, head_sha1))
@@ -202,11 +201,10 @@ static int cmd_import(const char *line)
 	} else {
 		memset(&svndump_proc, 0, sizeof(struct child_process));
 		svndump_proc.out = -1;
-		argv_array_push(&svndump_argv, "svnrdump");
-		argv_array_push(&svndump_argv, "dump");
-		argv_array_push(&svndump_argv, url);
-		argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
-		svndump_proc.argv = svndump_argv.argv;
+		argv_array_push(&svndump_proc.args, "svnrdump");
+		argv_array_push(&svndump_proc.args, "dump");
+		argv_array_push(&svndump_proc.args, url);
+		argv_array_pushf(&svndump_proc.args, "-r%u:HEAD", startrev);
 
 		code = start_command(&svndump_proc);
 		if (code)
@@ -227,7 +225,6 @@ static int cmd_import(const char *line)
 		code = finish_command(&svndump_proc);
 		if (code)
 			warning("%s, returned %d", svndump_proc.argv[0], code);
-		argv_array_clear(&svndump_argv);
 	}
 
 	return 0;

-- 
2.0.0

Junio C Hamano· Jul 18, 2014, 19:10 UTC · re: René Scharfe · lore

Re: [PATCH] remote-testsvn: use internal argv_array of struct child_process in cmd_import()

René Scharfe <l.s.r@web.de> writes:

Show 5 quoted lines

> Use the existing argv_array member instead of providing our own.  This
> way we don't have to initialize or clean it up explicitly.
>
> Signed-off-by: Rene Scharfe <l.s.r@web.de>
> ---

The change below looks so trivial and I cannot offhand see why it would break t9020 in a reproducible way.

Puzzled...

Show 39 quoted lines

>  remote-testsvn.c | 11 ++++-------
>  1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/remote-testsvn.c b/remote-testsvn.c
> index 6be55cb..31415bd 100644
> --- a/remote-testsvn.c
> +++ b/remote-testsvn.c
> @@ -175,7 +175,6 @@ static int cmd_import(const char *line)
>  	char *note_msg;
>  	unsigned char head_sha1[20];
>  	unsigned int startrev;
> -	struct argv_array svndump_argv = ARGV_ARRAY_INIT;
>  	struct child_process svndump_proc;
>  
>  	if (read_ref(private_ref, head_sha1))
> @@ -202,11 +201,10 @@ static int cmd_import(const char *line)
>  	} else {
>  		memset(&svndump_proc, 0, sizeof(struct child_process));
>  		svndump_proc.out = -1;
> -		argv_array_push(&svndump_argv, "svnrdump");
> -		argv_array_push(&svndump_argv, "dump");
> -		argv_array_push(&svndump_argv, url);
> -		argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
> -		svndump_proc.argv = svndump_argv.argv;
> +		argv_array_push(&svndump_proc.args, "svnrdump");
> +		argv_array_push(&svndump_proc.args, "dump");
> +		argv_array_push(&svndump_proc.args, url);
> +		argv_array_pushf(&svndump_proc.args, "-r%u:HEAD", startrev);
>  
>  		code = start_command(&svndump_proc);
>  		if (code)
> @@ -227,7 +225,6 @@ static int cmd_import(const char *line)
>  		code = finish_command(&svndump_proc);
>  		if (code)
>  			warning("%s, returned %d", svndump_proc.argv[0], code);
> -		argv_array_clear(&svndump_argv);
>  	}
>  
>  	return 0;

René Scharfe· Jul 18, 2014, 19:30 UTC · re: Junio C Hamano · lore

Re: [PATCH] remote-testsvn: use internal argv_array of struct child_process in cmd_import()

Am 18.07.2014 21:10, schrieb Junio C Hamano:

Show 49 quoted lines

> René Scharfe <l.s.r@web.de> writes:
> 
>> Use the existing argv_array member instead of providing our own.  This
>> way we don't have to initialize or clean it up explicitly.
>>
>> Signed-off-by: Rene Scharfe <l.s.r@web.de>
>> ---
> 
> The change below looks so trivial and I cannot offhand see why it
> would break t9020 in a reproducible way.
> 
> Puzzled...
> 
>>   remote-testsvn.c | 11 ++++-------
>>   1 file changed, 4 insertions(+), 7 deletions(-)
>>
>> diff --git a/remote-testsvn.c b/remote-testsvn.c
>> index 6be55cb..31415bd 100644
>> --- a/remote-testsvn.c
>> +++ b/remote-testsvn.c
>> @@ -175,7 +175,6 @@ static int cmd_import(const char *line)
>>   	char *note_msg;
>>   	unsigned char head_sha1[20];
>>   	unsigned int startrev;
>> -	struct argv_array svndump_argv = ARGV_ARRAY_INIT;
>>   	struct child_process svndump_proc;
>>   
>>   	if (read_ref(private_ref, head_sha1))
>> @@ -202,11 +201,10 @@ static int cmd_import(const char *line)
>>   	} else {
>>   		memset(&svndump_proc, 0, sizeof(struct child_process));
>>   		svndump_proc.out = -1;
>> -		argv_array_push(&svndump_argv, "svnrdump");
>> -		argv_array_push(&svndump_argv, "dump");
>> -		argv_array_push(&svndump_argv, url);
>> -		argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
>> -		svndump_proc.argv = svndump_argv.argv;
>> +		argv_array_push(&svndump_proc.args, "svnrdump");
>> +		argv_array_push(&svndump_proc.args, "dump");
>> +		argv_array_push(&svndump_proc.args, url);
>> +		argv_array_pushf(&svndump_proc.args, "-r%u:HEAD", startrev);
>>   
>>   		code = start_command(&svndump_proc);
>>   		if (code)
>> @@ -227,7 +225,6 @@ static int cmd_import(const char *line)
>>   		code = finish_command(&svndump_proc);
>>   		if (code)
>>   			warning("%s, returned %d", svndump_proc.argv[0], code);
>> -		argv_array_clear(&svndump_argv);

Unfortunately I don't get a test failure, but I think I see what's wrong: The warning line above references the argv array after it was freed by finish_command. Ouch. Fixup below:

---
 remote-testsvn.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Show changes to remote-testsvn.c +5 −3

diff --git a/remote-testsvn.c b/remote-testsvn.c
index 31415bd..e3ad11b 100644
--- a/remote-testsvn.c
+++ b/remote-testsvn.c
@@ -176,6 +176,7 @@ static int cmd_import(const char *line)
 	unsigned char head_sha1[20];
 	unsigned int startrev;
 	struct child_process svndump_proc;
+	const char *command;
 
 	if (read_ref(private_ref, head_sha1))
 		startrev = 0;
@@ -199,16 +200,17 @@ static int cmd_import(const char *line)
 		if(dumpin_fd < 0)
 			die_errno("Couldn't open svn dump file %s.", url);
 	} else {
+		command = "svnrdump";
 		memset(&svndump_proc, 0, sizeof(struct child_process));
 		svndump_proc.out = -1;
-		argv_array_push(&svndump_proc.args, "svnrdump");
+		argv_array_push(&svndump_proc.args, command);
 		argv_array_push(&svndump_proc.args, "dump");
 		argv_array_push(&svndump_proc.args, url);
 		argv_array_pushf(&svndump_proc.args, "-r%u:HEAD", startrev);
 
 		code = start_command(&svndump_proc);
 		if (code)
-			die("Unable to start %s, code %d", svndump_proc.argv[0], code);
+			die("Unable to start %s, code %d", command, code);
 		dumpin_fd = svndump_proc.out;
 	}
 	/* setup marks file import/export */
@@ -224,7 +226,7 @@ static int cmd_import(const char *line)
 	if (!dump_from_file) {
 		code = finish_command(&svndump_proc);
 		if (code)
-			warning("%s, returned %d", svndump_proc.argv[0], code);
+			warning("%s, returned %d", command, code);
 	}
 
 	return 0;

-- 
2.0.2

René Scharfe· Jul 18, 2014, 19:55 UTC · re: René Scharfe · lore

[PATCH v2] remote-testsvn: use internal argv_array of struct child_process in cmd_import()

Use the existing argv_array member instead of providing our own. This way we don't have to initialize or clean it up explicitly. Because of that automatic cleanup, we need to keep our own reference to the command name instead of using .argv[0] to print the warning at the end.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
---
The added command pointer makes the patch more complicated, but I think
it still counts as a cleanup.

 remote-testsvn.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

Show changes to remote-testsvn.c +8 −9

diff --git a/remote-testsvn.c b/remote-testsvn.c
index 6be55cb..e3ad11b 100644
--- a/remote-testsvn.c
+++ b/remote-testsvn.c
@@ -175,8 +175,8 @@ static int cmd_import(const char *line)
 	char *note_msg;
 	unsigned char head_sha1[20];
 	unsigned int startrev;
-	struct argv_array svndump_argv = ARGV_ARRAY_INIT;
 	struct child_process svndump_proc;
+	const char *command;
 
 	if (read_ref(private_ref, head_sha1))
 		startrev = 0;
@@ -200,17 +200,17 @@ static int cmd_import(const char *line)
 		if(dumpin_fd < 0)
 			die_errno("Couldn't open svn dump file %s.", url);
 	} else {
+		command = "svnrdump";
 		memset(&svndump_proc, 0, sizeof(struct child_process));
 		svndump_proc.out = -1;
-		argv_array_push(&svndump_argv, "svnrdump");
-		argv_array_push(&svndump_argv, "dump");
-		argv_array_push(&svndump_argv, url);
-		argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
-		svndump_proc.argv = svndump_argv.argv;
+		argv_array_push(&svndump_proc.args, command);
+		argv_array_push(&svndump_proc.args, "dump");
+		argv_array_push(&svndump_proc.args, url);
+		argv_array_pushf(&svndump_proc.args, "-r%u:HEAD", startrev);
 
 		code = start_command(&svndump_proc);
 		if (code)
-			die("Unable to start %s, code %d", svndump_proc.argv[0], code);
+			die("Unable to start %s, code %d", command, code);
 		dumpin_fd = svndump_proc.out;
 	}
 	/* setup marks file import/export */
@@ -226,8 +226,7 @@ static int cmd_import(const char *line)
 	if (!dump_from_file) {
 		code = finish_command(&svndump_proc);
 		if (code)
-			warning("%s, returned %d", svndump_proc.argv[0], code);
-		argv_array_clear(&svndump_argv);
+			warning("%s, returned %d", command, code);
 	}
 
 	return 0;

-- 
2.0.2

Junio C Hamano· Jul 18, 2014, 21:18 UTC · re: René Scharfe · lore

Re: [PATCH v2] remote-testsvn: use internal argv_array of struct child_process in cmd_import()

René Scharfe <l.s.r@web.de> writes:

Show 9 quoted lines

> Use the existing argv_array member instead of providing our own.  This
> way we don't have to initialize or clean it up explicitly.  Because of
> that automatic cleanup, we need to keep our own reference to the
> command name instead of using .argv[0] to print the warning at the end.
>
> Signed-off-by: Rene Scharfe <l.s.r@web.de>
> ---
> The added command pointer makes the patch more complicated, but I think
> it still counts as a cleanup.

Surely. I'd move the "svnrdump" assignment to where the variable is defined, though; we do not switch what "command" to run depending on some computed conditions anyway.

Show 52 quoted lines

>
>  remote-testsvn.c | 17 ++++++++---------
>  1 file changed, 8 insertions(+), 9 deletions(-)
>
> diff --git a/remote-testsvn.c b/remote-testsvn.c
> index 6be55cb..e3ad11b 100644
> --- a/remote-testsvn.c
> +++ b/remote-testsvn.c
> @@ -175,8 +175,8 @@ static int cmd_import(const char *line)
>  	char *note_msg;
>  	unsigned char head_sha1[20];
>  	unsigned int startrev;
> -	struct argv_array svndump_argv = ARGV_ARRAY_INIT;
>  	struct child_process svndump_proc;
> +	const char *command;
>  
>  	if (read_ref(private_ref, head_sha1))
>  		startrev = 0;
> @@ -200,17 +200,17 @@ static int cmd_import(const char *line)
>  		if(dumpin_fd < 0)
>  			die_errno("Couldn't open svn dump file %s.", url);
>  	} else {
> +		command = "svnrdump";
>  		memset(&svndump_proc, 0, sizeof(struct child_process));
>  		svndump_proc.out = -1;
> -		argv_array_push(&svndump_argv, "svnrdump");
> -		argv_array_push(&svndump_argv, "dump");
> -		argv_array_push(&svndump_argv, url);
> -		argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
> -		svndump_proc.argv = svndump_argv.argv;
> +		argv_array_push(&svndump_proc.args, command);
> +		argv_array_push(&svndump_proc.args, "dump");
> +		argv_array_push(&svndump_proc.args, url);
> +		argv_array_pushf(&svndump_proc.args, "-r%u:HEAD", startrev);
>  
>  		code = start_command(&svndump_proc);
>  		if (code)
> -			die("Unable to start %s, code %d", svndump_proc.argv[0], code);
> +			die("Unable to start %s, code %d", command, code);
>  		dumpin_fd = svndump_proc.out;
>  	}
>  	/* setup marks file import/export */
> @@ -226,8 +226,7 @@ static int cmd_import(const char *line)
>  	if (!dump_from_file) {
>  		code = finish_command(&svndump_proc);
>  		if (code)
> -			warning("%s, returned %d", svndump_proc.argv[0], code);
> -		argv_array_clear(&svndump_argv);
> +			warning("%s, returned %d", command, code);
>  	}
>  
>  	return 0;

René Scharfe· Jul 18, 2014, 21:45 UTC · re: Junio C Hamano · lore

Re: [PATCH v2] remote-testsvn: use internal argv_array of struct child_process in cmd_import()

Am 18.07.2014 23:18, schrieb Junio C Hamano:

Show 15 quoted lines

> René Scharfe <l.s.r@web.de> writes:
>
>> Use the existing argv_array member instead of providing our own.  This
>> way we don't have to initialize or clean it up explicitly.  Because of
>> that automatic cleanup, we need to keep our own reference to the
>> command name instead of using .argv[0] to print the warning at the end.
>>
>> Signed-off-by: Rene Scharfe <l.s.r@web.de>
>> ---
>> The added command pointer makes the patch more complicated, but I think
>> it still counts as a cleanup.
>
> Surely.  I'd move the "svnrdump" assignment to where the variable is
> defined, though; we do not switch what "command" to run depending on
> some computed conditions anyway.

OK; I see you already did that in pu, thanks. My point was to allow the compiler to warn if the variable command was used in the case start_command was not actually called. That's probably too subtle to be useful.

Show 53 quoted lines

>
>>
>>   remote-testsvn.c | 17 ++++++++---------
>>   1 file changed, 8 insertions(+), 9 deletions(-)
>>
>> diff --git a/remote-testsvn.c b/remote-testsvn.c
>> index 6be55cb..e3ad11b 100644
>> --- a/remote-testsvn.c
>> +++ b/remote-testsvn.c
>> @@ -175,8 +175,8 @@ static int cmd_import(const char *line)
>>   	char *note_msg;
>>   	unsigned char head_sha1[20];
>>   	unsigned int startrev;
>> -	struct argv_array svndump_argv = ARGV_ARRAY_INIT;
>>   	struct child_process svndump_proc;
>> +	const char *command;
>>
>>   	if (read_ref(private_ref, head_sha1))
>>   		startrev = 0;
>> @@ -200,17 +200,17 @@ static int cmd_import(const char *line)
>>   		if(dumpin_fd < 0)
>>   			die_errno("Couldn't open svn dump file %s.", url);
>>   	} else {
>> +		command = "svnrdump";
>>   		memset(&svndump_proc, 0, sizeof(struct child_process));
>>   		svndump_proc.out = -1;
>> -		argv_array_push(&svndump_argv, "svnrdump");
>> -		argv_array_push(&svndump_argv, "dump");
>> -		argv_array_push(&svndump_argv, url);
>> -		argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
>> -		svndump_proc.argv = svndump_argv.argv;
>> +		argv_array_push(&svndump_proc.args, command);
>> +		argv_array_push(&svndump_proc.args, "dump");
>> +		argv_array_push(&svndump_proc.args, url);
>> +		argv_array_pushf(&svndump_proc.args, "-r%u:HEAD", startrev);
>>
>>   		code = start_command(&svndump_proc);
>>   		if (code)
>> -			die("Unable to start %s, code %d", svndump_proc.argv[0], code);
>> +			die("Unable to start %s, code %d", command, code);
>>   		dumpin_fd = svndump_proc.out;
>>   	}
>>   	/* setup marks file import/export */
>> @@ -226,8 +226,7 @@ static int cmd_import(const char *line)
>>   	if (!dump_from_file) {
>>   		code = finish_command(&svndump_proc);
>>   		if (code)
>> -			warning("%s, returned %d", svndump_proc.argv[0], code);
>> -		argv_array_clear(&svndump_argv);
>> +			warning("%s, returned %d", command, code);
>>   	}
>>
>>   	return 0;