[PATCH v4 09/11] trace: remove limitation on directory

[David Marchand]

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.march...@redhat.com>
Acked-by: Jerin Jacob <jer...@marvell.com>
Acked-by: Sunil Kumar Kori <sk...@marvell.com>
---
 lib/eal/common/eal_common_trace_utils.c | 68 +++++++++----------------
 lib/eal/common/eal_trace.h              |  5 +-
 2 files changed, 25 insertions(+), 48 deletions(-)

diff --git a/lib/eal/common/eal_common_trace_utils.c 
b/lib/eal/common/eal_common_trace_utils.c
index 72108d36a6..8561a0e198 100644
--- a/lib/eal/common/eal_common_trace_utils.c
+++ b/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;
-
-       remaining = sizeof(trace->dir) - trace->dir_offset;
-       rc = rte_strscpy(&trace->dir[0] + trace->dir_offset, str, remaining);
-       if (rc < 0)
-               goto fail;
+       char *dir;
+       int rc;
 
-       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;
 
diff --git a/lib/eal/common/eal_trace.h b/lib/eal/common/eal_trace.h
index 26a18a2c48..d66bcfe198 100644
--- a/lib/eal/common/eal_trace.h
+++ b/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;
-- 
2.37.3