Fix thread safety, input validation, and error handling (#6)

* Fix thread safety, input validation, and error handling

- session_manager.h: make frame_counter atomic for thread safety
- main.c: add --test-time CLI option for timed transmit runs
- config_reader.c: replace atoi with strtol, fix null-app check,
  handle PCI BDF regex compilation failure
- logger.c: guard level check with mutex, handle freopen failure
- test_config_reader.c: update null-app test to expect error return

* Fix cppcheck and shellcheck warnings

- mtl_tx.c: move null check before pointer arithmetic to fix
  nullPointerArithmeticRedundantCheck
- logger.c: assign freopen result back to file_fp to fix resourceLeak
- build.sh, test.sh: remove UTF-8 BOM (SC1082)

---------

Co-authored-by: roshan-ku <roshan.kumar@intel.com>
Co-authored-by: D M, Karthik <karthik.d.m@intel.com>

Author: 3 people

include/core/session_manager.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <stdatomic.h>
 #include <stdint.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -57,7 +58,7 @@ struct shared_decode_ctx {
   bool               start_ready;
 
   struct dvledtx_context* app;
-  uint32_t           frame_counter;   /* shared monotonic frame number      */
+  _Atomic uint32_t   frame_counter;   /* shared monotonic frame number      */
 };
 
 /* Video TX session context */

scripts/build.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/bash
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright 2026 Intel Corporation
 

scripts/test.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/bash
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright 2026 Intel Corporation
 

src/main.c

@@ -154,30 +154,42 @@ static bool validate_log_path(const char* path) {
 }
 
 static void print_help(const char* prog_name) {
-  LOG_INFO("Usage: %s --config <file>", prog_name);
+  LOG_INFO("Usage: %s --config <file> [options]", prog_name);
   LOG_INFO("Options:");
-  LOG_INFO("  -C, --config <file>   JSON config file (required)");
-  LOG_INFO("  -v, --version         Show version");
-  LOG_INFO("  --help                Show this help");
+  LOG_INFO("  -C, --config <file>       JSON config file (required)");
+  LOG_INFO("  -t, --test-time <secs>    Transmit for N seconds then exit (1..86400)");
+  LOG_INFO("  -v, --version             Show version");
+  LOG_INFO("  --help                    Show this help");
 }
 
 static int parse_args(struct dvledtx_context* ctx, int argc, char** argv) {
   static struct option long_options[] = {
-    {"config",  required_argument, 0, 'C'},
-    {"version", no_argument,       0, 'v'},
-    {"help",    no_argument,       0, '?'},
+    {"config",    required_argument, 0, 'C'},
+    {"test-time", required_argument, 0, 't'},
+    {"version",   no_argument,       0, 'v'},
+    {"help",      no_argument,       0, '?'},
     {0, 0, 0, 0}
   };
 
   ctx->config_file[0] = '\0';
 
   int c = 0, option_index = 0;
-  while ((c = getopt_long(argc, argv, "C:v?", long_options, &option_index)) != -1) {
+  while ((c = getopt_long(argc, argv, "C:t:v?", long_options, &option_index)) != -1) { /* flawfinder: ignore */
     switch (c) {
       case 'C':
         strncpy(ctx->config_file, optarg, sizeof(ctx->config_file) - 1);
         ctx->config_file[sizeof(ctx->config_file) - 1] = '\0';
         break;
+      case 't': {
+        char *endptr = NULL;
+        long val = strtol(optarg, &endptr, 10);
+        if (endptr == optarg || *endptr != '\0' || val <= 0 || val > 86400) {
+          LOG_ERROR("Invalid --test-time value '%s' (expected 1..86400)", optarg);
+          return -1;
+        }
+        ctx->test_time_s = (int)val;
+        break;
+      }
       case 'v':
         printf("dvledtx version %s\n", DVLEDTX_VERSION);
         exit(0);

src/mtl/mtl_tx.c

@@ -145,13 +145,13 @@ void mtl_copy_crop_to_frame(struct st_frame* dst, AVFrame* src,
    * Y/U/V planes are packed sequentially: Y then U then V, each with
    * tightly-packed rows (no line padding).  Compute the offsets manually. */
   uint8_t* dst_y = (uint8_t*)dst->addr[0];
+  if (!dst_y) return;
+
   uint8_t* dst_u = dst->addr[1] ? (uint8_t*)dst->addr[1]
                                  : dst_y + dst_y_stride * crop_h;
   uint8_t* dst_v = dst->addr[2] ? (uint8_t*)dst->addr[2]
                                  : dst_u + dst_c_stride * chroma_h;
 
-  if (!dst_y) return;
-
   /* Luma (Y) plane — full crop_h rows, crop_w samples wide */
   for (int line = 0; line < crop_h; line++)
     memcpy(dst_y + line * dst_y_stride,

src/util/config_reader.c

@@ -6,6 +6,8 @@
 #include "util/config_reader.h"
 #include "app_context.h"
 #include "util/logger.h"
+#include <errno.h>
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -94,7 +96,12 @@ static int extract_json_int(const char* start, const char* end, const char* key)
         if (pos >= end || *pos != ':') continue;
         pos++;
         while (pos < end && (*pos == ' ' || *pos == '\t' || *pos == '\n' || *pos == '\r')) pos++;
-        return atoi(pos);
+        char *endptr = NULL;
+        errno = 0;
+        long val = strtol(pos, &endptr, 10);
+        if (endptr == pos || errno == ERANGE || val < INT_MIN || val > INT_MAX)
+            return -1;
+        return (int)val;
     }
     return -1;
 }
@@ -391,15 +398,17 @@ int validate_tx_config(const struct dvledtx_config* config) {
         int reti = regcomp(&regex,
             "^[0-9a-fA-F]{4}:[0-9a-fA-F]{2}:[0-9a-fA-F]{2}\\.[0-9]$",
             REG_EXTENDED | REG_NOSUB);
-        if (reti == 0) {
-            reti = regexec(&regex, config->interface_name, 0, NULL, 0);
-            regfree(&regex);
-            if (reti != 0) {
-                LOG_ERROR("Invalid PCI BDF format '%s' "
-                       "(expected DDDD:DD:DD.D hex pattern)",
-                       config->interface_name);
-                return -1;
-            }
+        if (reti != 0) {
+            LOG_ERROR("Internal error: PCI BDF regex compilation failed");
+            return -1;
+        }
+        reti = regexec(&regex, config->interface_name, 0, NULL, 0);
+        regfree(&regex);
+        if (reti != 0) {
+            LOG_ERROR("Invalid PCI BDF format '%s' "
+                   "(expected DDDD:DD:DD.D hex pattern)",
+                   config->interface_name);
+            return -1;
         }
     }
 
@@ -546,7 +555,9 @@ int validate_tx_config(const struct dvledtx_config* config) {
 }
 
 int load_and_apply_config(struct dvledtx_context* app, const char* config_file) {
-    if (app == NULL || config_file == NULL || config_file[0] == '\0')
+    if (app == NULL)
+        return -1;
+    if (config_file == NULL || config_file[0] == '\0')
         return 0; /* no config file — keep CLI defaults */
 
     struct dvledtx_config config;

src/util/logger.c

@@ -103,7 +103,10 @@ log_level_t logger_get_level(void)
 
 bool logger_is_level_enabled(log_level_t level)
 {
-    return g_logger.initialized && (level <= g_logger.config.level);
+    pthread_mutex_lock(&g_logger.lock);
+    bool enabled = g_logger.initialized && (level <= g_logger.config.level);
+    pthread_mutex_unlock(&g_logger.lock);
+    return enabled;
 }
 
 void logger_log(log_level_t level, const char *file, int line,
@@ -156,7 +159,12 @@ void logger_log(log_level_t level, const char *file, int line,
     if (g_logger.config.enable_file && g_logger.file_fp) {
         /* If the file has reached 20 MB, truncate and start fresh */
         if (ftell(g_logger.file_fp) >= 20 * 1024 * 1024) {
-            freopen(g_logger.config.log_file, "w", g_logger.file_fp);
+            FILE *new_fp = freopen(g_logger.config.log_file, "w", g_logger.file_fp);
+            if (new_fp == NULL) {
+                g_logger.file_fp = NULL;
+            } else {
+                g_logger.file_fp = new_fp;
+            }
         }
         if (level == LOG_LEVEL_ERROR) {
             fprintf(g_logger.file_fp, "%s[%s:%d %s] %s\n",

tests/test_config_reader.c

@@ -956,10 +956,10 @@ static void test_parse_session_zero_crop_w_fails(void **state)
  * load_and_apply_config
  * ========================================================================== */
 
-static void test_load_and_apply_config_null_app_returns_zero(void **state)
+static void test_load_and_apply_config_null_app_returns_error(void **state)
 {
     (void)state;
-    assert_int_equal(load_and_apply_config(NULL, "any_file.json"), 0);
+    assert_int_equal(load_and_apply_config(NULL, "any_file.json"), -1);
 }
 
 static void test_load_and_apply_config_null_file_returns_zero(void **state)
@@ -1175,7 +1175,7 @@ int main(void)
         cmocka_unit_test(test_peek_log_file_strips_bare_control_chars),
 
         /* --- load_and_apply_config --- */
-        cmocka_unit_test(test_load_and_apply_config_null_app_returns_zero),
+        cmocka_unit_test(test_load_and_apply_config_null_app_returns_error),
         cmocka_unit_test(test_load_and_apply_config_null_file_returns_zero),
         cmocka_unit_test(test_load_and_apply_config_empty_file_returns_zero),
         cmocka_unit_test(test_load_and_apply_config_nonexistent_file_returns_minus1),