POC: SDL-backed audio path for ncplayer

CMakeLists.txt

@@ -116,6 +116,7 @@ pkg_check_modules(AVDEVICE REQUIRED libavdevice>=57.0)
 pkg_check_modules(AVFORMAT REQUIRED libavformat>=57.0)
 pkg_check_modules(AVUTIL REQUIRED libavutil>=56.0)
 pkg_check_modules(SWSCALE REQUIRED libswscale>=5.0)
+pkg_check_modules(SWRESAMPLE REQUIRED libswresample>=4.0)
 set_property(GLOBAL APPEND PROPERTY PACKAGES_FOUND FFMpeg)
 elseif(${USE_OIIO})
 pkg_check_modules(OPENIMAGEIO REQUIRED OpenImageIO>=2.1)
@@ -130,7 +131,7 @@ if(NOT WIN32)
 if(NOT ${USE_ASAN})
 add_compile_definitions(_FORTIFY_SOURCE=2)
 endif()
-add_compile_options(-Wformat -Werror=format-security)
+add_compile_options(-Wformat -Werror=format-security -Werror)
 endif()
 if(MSVC)
 add_compile_options(/W4)
@@ -320,6 +321,9 @@ endif()
 ############################################################################
 # libnotcurses (multimedia shared library+static library)
 file(GLOB NCSRCS CONFIGURE_DEPENDS src/media/*.c src/media/*.cpp)
+# Exclude audio-output.c from libnotcurses to avoid SDL2 being loaded at library load time
+# audio-output.c will be compiled separately for ncplayer only
+list(REMOVE_ITEM NCSRCS "${CMAKE_SOURCE_DIR}/src/media/audio-output.c")
 add_library(notcurses SHARED ${NCSRCS} ${COMPATSRC})
 if(${USE_STATIC})
 # can't build binaries against static notcurses until ffmpeg linking issues
@@ -378,6 +382,7 @@ target_include_directories(notcurses
     "${AVFORMAT_INCLUDE_DIRS}"
     "${AVUTIL_INCLUDE_DIRS}"
     "${SWSCALE_INCLUDE_DIRS}"
+    "${SWRESAMPLE_INCLUDE_DIRS}"
 )
 target_include_directories(notcurses-static
   PRIVATE
@@ -386,13 +391,15 @@ target_include_directories(notcurses-static
     "${AVFORMAT_STATIC_INCLUDE_DIRS}"
     "${AVUTIL_STATIC_INCLUDE_DIRS}"
     "${SWSCALE_STATIC_INCLUDE_DIRS}"
+    "${SWRESAMPLE_STATIC_INCLUDE_DIRS}"
 )
 target_link_libraries(notcurses
   PRIVATE
     "${AVCODEC_LIBRARIES}"
     "${AVDEVICE_LIBRARIES}"
     "${AVFORMAT_LIBRARIES}"
     "${SWSCALE_LIBRARIES}"
+    "${SWRESAMPLE_LIBRARIES}"
     "${AVUTIL_LIBRARIES}"
 )
 target_link_libraries(notcurses-static
@@ -401,6 +408,7 @@ target_link_libraries(notcurses-static
     "${AVDEVICE_STATIC_LIBRARIES}"
     "${AVFORMAT_STATIC_LIBRARIES}"
     "${SWSCALE_STATIC_LIBRARIES}"
+    "${SWRESAMPLE_STATIC_LIBRARIES}"
     "${AVUTIL_STATIC_LIBRARIES}"
 )
 target_link_directories(notcurses
@@ -409,6 +417,7 @@ target_link_directories(notcurses
     "${AVDEVICE_LIBRARY_DIRS}"
     "${AVFORMAT_LIBRARY_DIRS}"
     "${SWSCALE_LIBRARY_DIRS}"
+    "${SWRESAMPLE_LIBRARY_DIRS}"
     "${AVUTIL_LIBRARY_DIRS}"
 )
 target_link_directories(notcurses-static
@@ -417,6 +426,7 @@ target_link_directories(notcurses-static
     "${AVDEVICE_STATIC_LIBRARY_DIRS}"
     "${AVFORMAT_STATIC_LIBRARY_DIRS}"
     "${SWSCALE_STATIC_LIBRARY_DIRS}"
+    "${SWRESAMPLE_STATIC_LIBRARY_DIRS}"
     "${AVUTIL_STATIC_LIBRARY_DIRS}"
 )
 elseif(${USE_OIIO})
@@ -851,10 +861,23 @@ target_include_directories(ncplayer
     "${CMAKE_REQUIRED_INCLUDES}"
     "${PROJECT_BINARY_DIR}/include"
 )
+if(${USE_FFMPEG})
+target_sources(ncplayer PRIVATE "${CMAKE_SOURCE_DIR}/src/media/audio-output.c")
+endif()
 target_link_libraries(ncplayer
   PRIVATE
     notcurses++
+    notcurses
 )
+if(${USE_FFMPEG})
+target_link_libraries(ncplayer
+  PRIVATE
+    "${AVCODEC_LIBRARIES}"
+    "${AVFORMAT_LIBRARIES}"
+    "${AVUTIL_LIBRARIES}"
+    "${SWRESAMPLE_LIBRARIES}"
+)
+endif()
 endif()
 endif()
 else()

include/ncpp/Visual.hh

@@ -91,6 +91,16 @@ namespace ncpp
 			return error_guard (ncvisual_simple_streamer (visual, vopts, tspec, curry), -1);
 		}
 
+		bool seek (double seconds) const NOEXCEPT_MAYBE
+		{
+			return error_guard (ncvisual_seek (visual, seconds), -1);
+		}
+
+		int64_t frame_index () const NOEXCEPT_MAYBE
+		{
+			return ncvisual_frame_index (visual);
+		}
+
 		int polyfill (int y, int x, uint32_t rgba) const NOEXCEPT_MAYBE
 		{
 			return error_guard<int> (ncvisual_polyfill_yx (visual, y, x, rgba), -1);

include/notcurses/api.h

@@ -0,0 +1,9 @@
+#ifdef API
+#undef API
+#endif
+
+#ifdef __MINGW32__
+# define API __declspec(dllexport)
+#else
+# define API __attribute__((visibility("default")))
+#endif

include/notcurses/direct.h

@@ -2,6 +2,7 @@
 #define NOTCURSES_DIRECT
 
 #include <notcurses/notcurses.h>
+#include <notcurses/api.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -11,11 +12,6 @@ extern "C" {
 #define static API
 #endif
 
-#ifndef __MINGW32__
-#define API __attribute__((visibility("default")))
-#else
-#define API __declspec(dllexport)
-#endif
 #define ALLOC __attribute__((malloc)) __attribute__((warn_unused_result))
 
 // ncdirect_init() will call setlocale() to inspect the current locale. If

include/notcurses/nckeys.h

@@ -3,6 +3,7 @@
 
 #include <stdint.h>
 #include <stdbool.h>
+#include <notcurses/api.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -12,11 +13,6 @@ extern "C" {
 #define static API
 #endif
 
-#ifndef __MINGW32__
-#define API __attribute__((visibility("default")))
-#else
-#define API __declspec(dllexport)
-#endif
 #define ALLOC __attribute__((malloc)) __attribute__((warn_unused_result))
 
 // Synthesized input events, i.e. any input event we can report that isn't

include/notcurses/notcurses.h

@@ -15,6 +15,7 @@
 #include <notcurses/ncport.h>
 #include <notcurses/nckeys.h>
 #include <notcurses/ncseqs.h>
+#include <notcurses/api.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -28,11 +29,6 @@ extern "C" {
 #define static API
 #endif
 
-#ifndef __MINGW32__
-#define API __attribute__((visibility("default")))
-#else
-#define API __declspec(dllexport)
-#endif
 #define ALLOC __attribute__((malloc)) __attribute__((warn_unused_result))
 
 // Get a human-readable string describing the running Notcurses version.
@@ -3435,6 +3431,15 @@ API int ncvisual_decode(struct ncvisual* nc)
 API int ncvisual_decode_loop(struct ncvisual* nc)
   __attribute__ ((nonnull (1)));
 
+// Seek within a visual by the provided number of seconds. Positive values move
+// forward, negative backwards. Not all backends support seeking.
+API int ncvisual_seek(struct ncvisual* n, double seconds)
+  __attribute__ ((nonnull (1)));
+
+// Return zero-based index of last decoded frame, or -1 if unavailable
+API int64_t ncvisual_frame_index(const struct ncvisual* n)
+  __attribute__ ((nonnull (1)));
+
 // Rotate the visual 'rads' radians. Only M_PI/2 and -M_PI/2 are supported at
 // the moment, but this might change in the future.
 API int ncvisual_rotate(struct ncvisual* n, double rads)

src/lib/debug.c

@@ -1,6 +1,7 @@
 #include "internal.h"
+#include <notcurses/api.h>
 
-ncloglevel_e loglevel = NCLOGLEVEL_SILENT;
+API ncloglevel_e loglevel = NCLOGLEVEL_SILENT;
 
 void notcurses_debug(const notcurses* nc, FILE* debugfp){
   fbuf f;

src/lib/internal.h

@@ -8,6 +8,7 @@
 #include "notcurses/ncport.h"
 #include "notcurses/notcurses.h"
 #include "notcurses/direct.h"
+#include <notcurses/api.h>
 // KEY_EVENT is defined by both ncurses.h (prior to 6.3) and wincon.h. since we
 // don't use either definition, kill it before inclusion of ncurses.h.
 #undef KEY_EVENT
@@ -38,11 +39,6 @@
 #include "lib/gpm.h"
 
 
-#ifndef __MINGW32__
-#define API __attribute__((visibility("default")))
-#else
-#define API __declspec(dllexport)
-#endif
 #define ALLOC __attribute__((malloc)) __attribute__((warn_unused_result))
 
 #ifdef __cplusplus
@@ -1807,6 +1803,8 @@ typedef struct ncvisual_implementation {
   int rowalign; // rowstride base, can be 0 for no padding
   // do a persistent resize, changing the ncv itself
   int (*visual_resize)(struct ncvisual* ncv, unsigned rows, unsigned cols);
+  int (*visual_seek)(struct ncvisual* ncv, double seconds);
+  int64_t (*visual_frame_index)(const struct ncvisual* ncv);
   void (*visual_destroy)(struct ncvisual* ncv);
   bool canopen_images;
   bool canopen_videos;

src/lib/visual.c

@@ -50,6 +50,20 @@ int ncvisual_decode_loop(ncvisual* nc){
   return visual_implementation->visual_decode_loop(nc);
 }
 
+int ncvisual_seek(ncvisual* nc, double seconds){
+  if(!visual_implementation->visual_seek){
+    return -1;
+  }
+  return visual_implementation->visual_seek(nc, seconds);
+}
+
+int64_t ncvisual_frame_index(const ncvisual* nc){
+  if(!visual_implementation->visual_frame_index){
+    return -1;
+  }
+  return visual_implementation->visual_frame_index(nc);
+}
+
 ncvisual* ncvisual_from_file(const char* filename){
   if(!visual_implementation->visual_from_file){
     return NULL;