build: allow pattern matching for BITCOINKERNEL_LIB

This simplifies ci/build system setup by not having to specify
the exact filename, which can vary across platforms.

Author: stickies-v

CMakeLists.txt

@@ -12,8 +12,12 @@ set(BITCOIN_TARGET "" CACHE STRING "Host triple for cross compilation, enables d
 
 add_library(bitcoinkernel SHARED IMPORTED)
 if(DEFINED ENV{BITCOINKERNEL_LIB})
-    message(STATUS "Using bitcoinkernel library from BITCOINKERNEL_LIB: $ENV{BITCOINKERNEL_LIB}")
-    set(BITCOINKERNEL_PATH "$ENV{BITCOINKERNEL_LIB}")
+    file(GLOB BITCOINKERNEL_MATCHES "$ENV{BITCOINKERNEL_LIB}")
+    list(LENGTH BITCOINKERNEL_MATCHES MATCH_COUNT)
+    if(NOT MATCH_COUNT EQUAL 1)
+        message(FATAL_ERROR "Expected exactly one match for $ENV{BITCOINKERNEL_LIB}, found ${MATCH_COUNT}")
+    endif()
+    list(GET BITCOINKERNEL_MATCHES 0 BITCOINKERNEL_PATH)
 else()
     set(BITCOIN_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/depend/bitcoin")
     message(STATUS "Building bitcoinkernel from source in ${BITCOIN_SOURCE_DIR}")