tools: add ug_stub.c to substitute host.cpp

Because host.cpp has extensive dependencies on UG internals, it is a
bit tricky to link-in. Created a replacement instead.

src/libavcodec/lavc_common.c

@@ -178,18 +178,13 @@ static void av_log_ug_callback(void *avcl, int av_level, const char *fmt, va_lis
         buf[0] = '\0';
 }
 
-#ifdef HAVE_CONFIG_H // built inside UG
 ADD_TO_PARAM("lavc-log-level",
                 "* lavc-log-level=<num>\n"
                 "  Set libavcodec log level (FFmpeg range semantics, bypasses UG logger)\n"
                 " - 'D' - use FFmpeg default log handler\n");
-#endif
 /// Sets specified log level either given explicitly or from UG-wide log_level
 void ug_set_av_logging() {
-        const char *param = NULL;
-#ifdef HAVE_CONFIG_H // built inside UG
-        param = get_commandline_param("lavc-log-level");
-#endif
+        const char *param = get_commandline_param("lavc-log-level");
         if (param == NULL) {
                 av_log_set_callback(av_log_ug_callback);
                 return;

src/utils/color_out.cpp

@@ -125,21 +125,16 @@ static bool isMsysPty(int fd) {
 }
 #endif // defined _WIN32
 
-// conditional include here (and below) is to allow compilation outside UG
-// without the need to link with host.o, which seems to be tricky
-#ifdef HAVE_CONFIG_H
 ADD_TO_PARAM("log-color", "* log-color[=no]\n"
                  "  Force enable/disable ANSI text formatting.\n");
 ADD_TO_PARAM("log-nocolor", "* log-nocolor\n"
                  "  Force disable ANSI text formatting.\n");
-#endif
 /**
  * @returns whether stdout can process ANSI escape sequences
  */
 static bool
 is_output_color()
 {
-#ifdef HAVE_CONFIG_H
         const char *const param_val = get_commandline_param("log-color");
         if (param_val != nullptr) {
                 return strcmp(param_val, "no") != 0;
@@ -150,7 +145,6 @@ is_output_color()
                                  "'log-color=no' instead\n");
                 return false;
         }
-#endif
         const char *env_val = getenv("ULTRAGRID_COLOR_OUT");
         if (env_val != nullptr && strlen(env_val) > 0) {
                 return strcmp(env_val, "0") != 0;

tools/Makefile

@@ -15,7 +15,8 @@ TARGETS=astat_lib astat_test benchmark_ff_convs convert decklink_temperature \
 
 COMMON_OBJS = src/color.o src/debug.o src/video_codec.o src/pixfmt_conv.o \
 	src/utils/color_out.o src/utils/misc.o src/video_frame.o \
-	src/utils/pam.o src/utils/y4m.o
+	src/utils/pam.o src/utils/y4m.o \
+	ug_stub.o
 
 OBJS=$(shell find . -name '*.o')
 

tools/ug_stub.c

@@ -0,0 +1,21 @@
+/**
+ * @file
+ * replacement for UltraGrid functions/global objects that are not linked-in,
+ * usually the ones located in host.cpp
+ */
+
+#include <stddef.h>
+
+const char *
+get_commandline_param(const char *key)
+{
+        (void) key;
+        return NULL;
+}
+
+void
+register_param(const char *param, const char *doc)
+{
+        (void) param;
+        (void) doc;
+}