From 020a3e4b425a6efdda28c0ebd08891d9178fe471 Mon Sep 17 00:00:00 2001
From: Chris Robinson <chris.kcat@gmail.com>
Date: Fri, 6 Dec 2024 03:30:28 -0800
Subject: [PATCH] Get ffmpeg library versions when pkg-config is unavailable

---
 cmake/FindFFmpeg.cmake | 33 +++++++++++++++++++++++++++++++--
 1 file changed, 31 insertions(+), 2 deletions(-)

diff --git a/cmake/FindFFmpeg.cmake b/cmake/FindFFmpeg.cmake
index 26ed4d2faf..190c2c56c1 100644
--- a/cmake/FindFFmpeg.cmake
+++ b/cmake/FindFFmpeg.cmake
@@ -80,8 +80,37 @@ macro(find_component _component _pkgconfig _library _header)
             ${PC_LIB${_component}_LIBRARY_DIRS}
     )
 
-    set(${_component}_VERSION     ${PC_${_component}_VERSION}      CACHE STRING "The ${_component} version number." FORCE)
-    set(${_component}_DEFINITIONS ${PC_${_component}_CFLAGS_OTHER} CACHE STRING "The ${_component} CFLAGS." FORCE)
+    if(DEFINED ${PC_${_component}_VERSION})
+        set(${_component}_VERSION ${PC_${_component}_VERSION} CACHE STRING
+            "The ${_component} version number." FORCE)
+    else()
+        if(EXISTS "${${_component}_INCLUDE_DIRS}/${_pkgconfig}/version_major.h")
+            file(STRINGS "${${_component}_INCLUDE_DIRS}/${_pkgconfig}/version_major.h" majorver
+                REGEX "^#define[ \t]+LIB${_component}_VERSION_MAJOR[ \t]+[0-9]+$")
+        else()
+            file(STRINGS "${${_component}_INCLUDE_DIRS}/${_pkgconfig}/version.h" majorver
+                REGEX "^#define[ \t]+LIB${_component}_VERSION_MAJOR[ \t]+[0-9]+$")
+        endif()
+        file(STRINGS "${${_component}_INCLUDE_DIRS}/${_pkgconfig}/version.h" minorver
+            REGEX "^#define[ \t]+LIB${_component}_VERSION_MINOR[ \t]+[0-9]+$")
+        file(STRINGS "${${_component}_INCLUDE_DIRS}/${_pkgconfig}/version.h" microver
+            REGEX "^#define[ \t]+LIB${_component}_VERSION_MICRO[ \t]+[0-9]+$")
+
+        string(REGEX REPLACE "^#define[ \t]+LIB${_component}_VERSION_MAJOR[ \t]+([0-9]+)$" "\\1"
+            majorver "${majorver}")
+        string(REGEX REPLACE "^#define[ \t]+LIB${_component}_VERSION_MINOR[ \t]+([0-9]+)$" "\\1"
+            minorver "${minorver}")
+        string(REGEX REPLACE "^#define[ \t]+LIB${_component}_VERSION_MICRO[ \t]+([0-9]+)$" "\\1"
+            microver "${microver}")
+
+        set(${_component}_VERSION "${majorver}.${minorver}.${microver}" CACHE STRING
+            "The ${_component} version number." FORCE)
+        unset(microver)
+        unset(minorver)
+        unset(majorver)
+    endif()
+    set(${_component}_DEFINITIONS ${PC_${_component}_CFLAGS_OTHER} CACHE STRING
+        "The ${_component} CFLAGS." FORCE)
 
     set_component_found(${_component})