trace: remove limitation on directory

Remove arbitrary limit on 12 characters of the file prefix used for the
directory where to store the traces.
Simplify the code by relying on dynamic allocations.

Signed-off-by: David Marchand <david.marchand@redhat.com>
Acked-by: Jerin Jacob <jerinj@marvell.com>
Acked-by: Sunil Kumar Kori <skori@marvell.com>

lib/eal/common/eal_common_trace_utils.c

@@ -87,11 +87,11 @@ trace_uuid_generate(void)
 }
 
 static int
-trace_session_name_generate(char *trace_dir)
+trace_session_name_generate(char **trace_dir)
 {
+	char date[sizeof("YYYY-mm-dd-AM-HH-MM-SS")];
 	struct tm *tm_result;
 	time_t tm;
-	int rc;
 
 	tm = time(NULL);
 	if ((int)tm == -1)
@@ -101,38 +101,32 @@ trace_session_name_generate(char *trace_dir)
 	if (tm_result == NULL)
 		goto fail;
 
-	rc = rte_strscpy(trace_dir, eal_get_hugefile_prefix(),
-			TRACE_PREFIX_LEN);
-	if (rc == -E2BIG)
-		rc = TRACE_PREFIX_LEN - 1;
-	trace_dir[rc++] = '-';
-
-	rc = strftime(trace_dir + rc, TRACE_DIR_STR_LEN - rc,
-			"%Y-%m-%d-%p-%I-%M-%S", tm_result);
-	if (rc == 0) {
+	if (strftime(date, sizeof(date), "%Y-%m-%d-%p-%I-%M-%S", tm_result) == 0) {
 		errno = ENOSPC;
 		goto fail;
 	}
 
-	return rc;
+	if (asprintf(trace_dir, "%s-%s", eal_get_hugefile_prefix(), date) == -1)
+		goto fail;
+
+	return 0;
 fail:
 	rte_errno = errno;
-	return -rte_errno;
+	return -1;
 }
 
 static int
 trace_dir_update(const char *str)
 {
 	struct trace *trace = trace_obj_get();
-	int rc, remaining;
+	char *dir;
+	int rc;
 
-	remaining = sizeof(trace->dir) - trace->dir_offset;
-	rc = rte_strscpy(&trace->dir[0] + trace->dir_offset, str, remaining);
-	if (rc < 0)
-		goto fail;
-
-	trace->dir_offset += rc;
-fail:
+	rc = asprintf(&dir, "%s%s", trace->dir != NULL ? trace->dir : "", str);
+	if (rc != -1) {
+		free(trace->dir);
+		trace->dir = dir;
+	}
 	return rc;
 }
 
@@ -246,22 +240,15 @@ eal_trace_mode_args_save(const char *val)
 int
 eal_trace_dir_args_save(char const *val)
 {
-	struct trace *trace = trace_obj_get();
 	char *dir_path;
 	int rc;
 
-	if (strlen(val) >= sizeof(trace->dir) - 1) {
-		trace_err("input string is too big");
-		return -ENAMETOOLONG;
-	}
-
 	if (asprintf(&dir_path, "%s/", val) == -1) {
 		trace_err("failed to copy directory: %s", strerror(errno));
 		return -ENOMEM;
 	}
 
 	rc = trace_dir_update(dir_path);
-
 	free(dir_path);
 	return rc;
 }
@@ -289,10 +276,8 @@ trace_epoch_time_save(void)
 }
 
 static int
-trace_dir_default_path_get(char *dir_path)
+trace_dir_default_path_get(char **dir_path)
 {
-	struct trace *trace = trace_obj_get();
-	uint32_t size = sizeof(trace->dir);
 	struct passwd *pwd;
 	char *home_dir;
 
@@ -308,8 +293,8 @@ trace_dir_default_path_get(char *dir_path)
 	}
 
 	/* Append dpdk-traces to directory */
-	if (snprintf(dir_path, size, "%s/dpdk-traces/", home_dir) < 0)
-		return -ENAMETOOLONG;
+	if (asprintf(dir_path, "%s/dpdk-traces/", home_dir) == -1)
+		return -ENOMEM;
 
 	return 0;
 }
@@ -318,25 +303,19 @@ static int
 trace_mkdir(void)
 {
 	struct trace *trace = trace_obj_get();
-	char session[TRACE_DIR_STR_LEN];
 	static bool already_done;
-	char *dir_path;
+	char *session;
 	int rc;
 
 	if (already_done)
 		return 0;
 
-	if (!trace->dir_offset) {
-		dir_path = calloc(1, sizeof(trace->dir));
-		if (dir_path == NULL) {
-			trace_err("fail to allocate memory");
-			return -ENOMEM;
-		}
+	if (trace->dir == NULL) {
+		char *dir_path;
 
-		rc = trace_dir_default_path_get(dir_path);
+		rc = trace_dir_default_path_get(&dir_path);
 		if (rc < 0) {
 			trace_err("fail to get default path");
-			free(dir_path);
 			return rc;
 		}
 
@@ -354,10 +333,11 @@ trace_mkdir(void)
 		return -rte_errno;
 	}
 
-	rc = trace_session_name_generate(session);
+	rc = trace_session_name_generate(&session);
 	if (rc < 0)
 		return rc;
 	rc = trace_dir_update(session);
+	free(session);
 	if (rc < 0)
 		return rc;
 

lib/eal/common/eal_trace.h

@@ -22,8 +22,6 @@
 #define trace_crit(fmt, args...) \
 	RTE_LOG(CRIT, EAL, "%s():%u " fmt "\n", __func__, __LINE__, ## args)
 
-#define TRACE_PREFIX_LEN 12
-#define TRACE_DIR_STR_LEN (sizeof("YYYY-mm-dd-AM-HH-MM-SS") + TRACE_PREFIX_LEN)
 #define TRACE_CTF_MAGIC 0xC1FC1FC1
 #define TRACE_MAX_ARGS	32
 
@@ -50,8 +48,7 @@ struct trace_arg {
 };
 
 struct trace {
-	char dir[PATH_MAX];
-	int dir_offset;
+	char *dir;
 	int register_errno;
 	uint32_t status;
 	enum rte_trace_mode mode;