[v2,6/8] trace-cmd: Move plog() function to libtracecmd.
diff mbox series

Message ID 20190814084712.28188-7-tz.stoyanov@gmail.com
State Superseded
Delegated to: Steven Rostedt
Headers show
Series
  • Separate trace-cmd and libtracecmd code
Related show

Commit Message

Tzvetomir Stoyanov (VMware) Aug. 14, 2019, 8:47 a.m. UTC
plog() function writes logs into a log file. It is used in
libtracecmd and its implementation should be there.
The function is moved from trace-cmd into the library, and 2
additional APIs are implemented:
	int trace_set_log_file(char *logfile); - use it to set
the log file.
	void plog_error(const char *fmt, ...); - use it to log
an error message into the file.

The plog() function is used also from pdie() in trace-cmd.
pdie() depends on trace-cmd context and cannot be moved to
the library. It is reimplemented as macros, in order to utilize
the new plog() library function.

Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
 include/trace-cmd/trace-cmd.h |  4 ++
 include/trace-cmd/trace-msg.h |  3 --
 lib/trace-cmd/trace-util.c    | 71 +++++++++++++++++++++++++++++++++++
 tracecmd/trace-listen.c       | 69 ++++------------------------------
 4 files changed, 83 insertions(+), 64 deletions(-)

Comments

Steven Rostedt Aug. 28, 2019, 8:15 p.m. UTC | #1
On Wed, 14 Aug 2019 11:47:06 +0300
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:

> plog() function writes logs into a log file. It is used in
> libtracecmd and its implementation should be there.
> The function is moved from trace-cmd into the library, and 2
> additional APIs are implemented:
> 	int trace_set_log_file(char *logfile); - use it to set
> the log file.
> 	void plog_error(const char *fmt, ...); - use it to log
> an error message into the file.
> 
> The plog() function is used also from pdie() in trace-cmd.
> pdie() depends on trace-cmd context and cannot be moved to
> the library. It is reimplemented as macros, in order to utilize
> the new plog() library function.
> 
> Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
> ---
>  include/trace-cmd/trace-cmd.h |  4 ++
>  include/trace-cmd/trace-msg.h |  3 --
>  lib/trace-cmd/trace-util.c    | 71 +++++++++++++++++++++++++++++++++++
>  tracecmd/trace-listen.c       | 69 ++++------------------------------
>  4 files changed, 83 insertions(+), 64 deletions(-)
> 
> diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
> index b96de04..8db0686 100644
> --- a/include/trace-cmd/trace-cmd.h
> +++ b/include/trace-cmd/trace-cmd.h
> @@ -398,6 +398,10 @@ struct hook_list {
>  struct hook_list *tracecmd_create_event_hook(const char *arg);
>  void tracecmd_free_hooks(struct hook_list *hooks);
>  
> +void plog(const char *fmt, ...);
> +void plog_error(const char *fmt, ...);

If these are going to become visible in the library, then they need to
have a prefix "tracecmd_" attached to them.

> +int trace_set_log_file(char *logfile);
> +
>  /* --- Hack! --- */
>  int tracecmd_blk_hack(struct tracecmd_input *handle);
>  
> diff --git a/include/trace-cmd/trace-msg.h b/include/trace-cmd/trace-msg.h
> index b7fe10b..aab8a69 100644
> --- a/include/trace-cmd/trace-msg.h
> +++ b/include/trace-cmd/trace-msg.h
> @@ -12,7 +12,4 @@
>  
>  extern unsigned int page_size;
>  
> -void plog(const char *fmt, ...);
> -void pdie(const char *fmt, ...);
> -
>  #endif /* _TRACE_MSG_H_ */
> diff --git a/lib/trace-cmd/trace-util.c b/lib/trace-cmd/trace-util.c
> index b5ce84f..8c1a0a0 100644
> --- a/lib/trace-cmd/trace-util.c
> +++ b/lib/trace-cmd/trace-util.c
> @@ -31,6 +31,8 @@ int tracecmd_disable_plugins;
>  static int tracecmd_quiet;
>  static bool tracecmd_debug;
>  
> +static FILE *trace_logfp;

As this is a static variable, we only need to call it logfp.

> +
>  static struct registered_plugin_options {
>  	struct registered_plugin_options	*next;
>  	struct tep_plugin_option			*options;
> @@ -1716,3 +1718,72 @@ void __weak *malloc_or_die(unsigned int size)
>  		die("malloc");
>  	return data;
>  }
> +
> +#define LOG_BUF_SIZE 1024
> +static void __plog(const char *prefix, const char *fmt, va_list ap, FILE *fp)
> +{
> +	static int newline = 1;
> +	char buf[LOG_BUF_SIZE];
> +	int r;
> +
> +	r = vsnprintf(buf, LOG_BUF_SIZE, fmt, ap);
> +
> +	if (r > LOG_BUF_SIZE)
> +		r = LOG_BUF_SIZE;
> +
> +	if (trace_logfp) {
> +		if (newline)
> +			fprintf(trace_logfp, "[%d]%s%.*s", getpid(), prefix, r, buf);
> +		else
> +			fprintf(trace_logfp, "[%d]%s%.*s", getpid(), prefix, r, buf);
> +		newline = buf[r - 1] == '\n';
> +		fflush(trace_logfp);
> +		return;
> +	}
> +
> +	fprintf(fp, "%.*s", r, buf);
> +}
> +
> +void plog(const char *fmt, ...)
> +{
> +	va_list ap;
> +
> +	va_start(ap, fmt);
> +	__plog("", fmt, ap, stdout);
> +	va_end(ap);
> +	/* Make sure it gets to the screen, in case we crash afterward */
> +	fflush(stdout);
> +}
> +
> +void plog_error(const char *fmt, ...)
> +{
> +	va_list ap;
> +	char *str = "";
> +
> +	va_start(ap, fmt);
> +	__plog("Error: ", fmt, ap, stderr);
> +	va_end(ap);
> +	if (errno)
> +		str = strerror(errno);
> +	if (trace_logfp)
> +		fprintf(trace_logfp, "\n%s\n", str);
> +	else
> +		fprintf(stderr, "\n%s\n", str);
> +}
> +
> +/**
> + * trace_set_log_file - Set file for logging
> + * @logfile: Name of the log file
> + *
> + * Returns 0 on successful completion or -1 in case of error
> + */
> +int trace_set_log_file(char *logfile)

Should it be called tracecmd_set_logfile()?

-- Steve

> +{
> +	if (trace_logfp)
> +		fclose(trace_logfp);
> +	trace_logfp = fopen(logfile, "w");
> +	if (!trace_logfp)
> +		return -1;
> +	return 0;
> +}
> +

Patch
diff mbox series

diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
index b96de04..8db0686 100644
--- a/include/trace-cmd/trace-cmd.h
+++ b/include/trace-cmd/trace-cmd.h
@@ -398,6 +398,10 @@  struct hook_list {
 struct hook_list *tracecmd_create_event_hook(const char *arg);
 void tracecmd_free_hooks(struct hook_list *hooks);
 
+void plog(const char *fmt, ...);
+void plog_error(const char *fmt, ...);
+int trace_set_log_file(char *logfile);
+
 /* --- Hack! --- */
 int tracecmd_blk_hack(struct tracecmd_input *handle);
 
diff --git a/include/trace-cmd/trace-msg.h b/include/trace-cmd/trace-msg.h
index b7fe10b..aab8a69 100644
--- a/include/trace-cmd/trace-msg.h
+++ b/include/trace-cmd/trace-msg.h
@@ -12,7 +12,4 @@ 
 
 extern unsigned int page_size;
 
-void plog(const char *fmt, ...);
-void pdie(const char *fmt, ...);
-
 #endif /* _TRACE_MSG_H_ */
diff --git a/lib/trace-cmd/trace-util.c b/lib/trace-cmd/trace-util.c
index b5ce84f..8c1a0a0 100644
--- a/lib/trace-cmd/trace-util.c
+++ b/lib/trace-cmd/trace-util.c
@@ -31,6 +31,8 @@  int tracecmd_disable_plugins;
 static int tracecmd_quiet;
 static bool tracecmd_debug;
 
+static FILE *trace_logfp;
+
 static struct registered_plugin_options {
 	struct registered_plugin_options	*next;
 	struct tep_plugin_option			*options;
@@ -1716,3 +1718,72 @@  void __weak *malloc_or_die(unsigned int size)
 		die("malloc");
 	return data;
 }
+
+#define LOG_BUF_SIZE 1024
+static void __plog(const char *prefix, const char *fmt, va_list ap, FILE *fp)
+{
+	static int newline = 1;
+	char buf[LOG_BUF_SIZE];
+	int r;
+
+	r = vsnprintf(buf, LOG_BUF_SIZE, fmt, ap);
+
+	if (r > LOG_BUF_SIZE)
+		r = LOG_BUF_SIZE;
+
+	if (trace_logfp) {
+		if (newline)
+			fprintf(trace_logfp, "[%d]%s%.*s", getpid(), prefix, r, buf);
+		else
+			fprintf(trace_logfp, "[%d]%s%.*s", getpid(), prefix, r, buf);
+		newline = buf[r - 1] == '\n';
+		fflush(trace_logfp);
+		return;
+	}
+
+	fprintf(fp, "%.*s", r, buf);
+}
+
+void plog(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	__plog("", fmt, ap, stdout);
+	va_end(ap);
+	/* Make sure it gets to the screen, in case we crash afterward */
+	fflush(stdout);
+}
+
+void plog_error(const char *fmt, ...)
+{
+	va_list ap;
+	char *str = "";
+
+	va_start(ap, fmt);
+	__plog("Error: ", fmt, ap, stderr);
+	va_end(ap);
+	if (errno)
+		str = strerror(errno);
+	if (trace_logfp)
+		fprintf(trace_logfp, "\n%s\n", str);
+	else
+		fprintf(stderr, "\n%s\n", str);
+}
+
+/**
+ * trace_set_log_file - Set file for logging
+ * @logfile: Name of the log file
+ *
+ * Returns 0 on successful completion or -1 in case of error
+ */
+int trace_set_log_file(char *logfile)
+{
+	if (trace_logfp)
+		fclose(trace_logfp);
+	trace_logfp = fopen(logfile, "w");
+	if (!trace_logfp)
+		return -1;
+	return 0;
+}
+
diff --git a/tracecmd/trace-listen.c b/tracecmd/trace-listen.c
index 3cbee67..e0dcd71 100644
--- a/tracecmd/trace-listen.c
+++ b/tracecmd/trace-listen.c
@@ -34,8 +34,6 @@  static char *output_dir;
 static char *default_output_file = "trace";
 static char *output_file;
 
-static FILE *logfp;
-
 static int backlog = 5;
 
 static int do_daemon;
@@ -44,6 +42,13 @@  static int do_daemon;
 static struct tracecmd_msg_handle *stop_msg_handle;
 static bool done;
 
+#define pdie(fmt, ...)				\
+	do {					\
+		plog_error(fmt, ##__VA_ARGS__);	\
+		remove_pid_file();		\
+		exit(-1);			\
+	} while (0)
+
 #define  TEMP_FILE_STR "%s.%s:%s.cpu%d", output_file, host, port, cpu
 static char *get_temp_file(const char *host, const char *port, int cpu)
 {
@@ -114,43 +119,6 @@  static void finish(int sig)
 	done = true;
 }
 
-#define LOG_BUF_SIZE 1024
-static void __plog(const char *prefix, const char *fmt, va_list ap,
-		   FILE *fp)
-{
-	static int newline = 1;
-	char buf[LOG_BUF_SIZE];
-	int r;
-
-	r = vsnprintf(buf, LOG_BUF_SIZE, fmt, ap);
-
-	if (r > LOG_BUF_SIZE)
-		r = LOG_BUF_SIZE;
-
-	if (logfp) {
-		if (newline)
-			fprintf(logfp, "[%d]%s%.*s", getpid(), prefix, r, buf);
-		else
-			fprintf(logfp, "[%d]%s%.*s", getpid(), prefix, r, buf);
-		newline = buf[r - 1] == '\n';
-		fflush(logfp);
-		return;
-	}
-
-	fprintf(fp, "%.*s", r, buf);
-}
-
-void plog(const char *fmt, ...)
-{
-	va_list ap;
-
-	va_start(ap, fmt);
-	__plog("", fmt, ap, stdout);
-	va_end(ap);
-	/* Make sure it gets to the screen, in case we crash afterward */
-	fflush(stdout);
-}
-
 static void make_pid_name(int mode, char *buf)
 {
 	snprintf(buf, PATH_MAX, VAR_RUN_DIR "/trace-cmd-net.pid");
@@ -169,26 +137,6 @@  static void remove_pid_file(void)
 	unlink(buf);
 }
 
-void pdie(const char *fmt, ...)
-{
-	va_list ap;
-	char *str = "";
-
-	va_start(ap, fmt);
-	__plog("Error: ", fmt, ap, stderr);
-	va_end(ap);
-	if (errno)
-		str = strerror(errno);
-	if (logfp)
-		fprintf(logfp, "\n%s\n", str);
-	else
-		fprintf(stderr, "\n%s\n", str);
-
-	remove_pid_file();
-
-	exit(-1);
-}
-
 static int process_udp_child(int sfd, const char *host, const char *port,
 			     int cpu, int page_size, int use_tcp)
 {
@@ -1030,8 +978,7 @@  void trace_listen(int argc, char **argv)
 
 	if (logfile) {
 		/* set the writes to a logfile instead */
-		logfp = fopen(logfile, "w");
-		if (!logfp)
+		if (trace_set_log_file(logfile) < 0)
 			die("creating log file %s", logfile);
 	}