From: Jakub Jirutka <jakub@jirutka.cz>
Date: Thu, 21 Jul 2022 17:38:00 +0200
Subject: [PATCH] Set SONAME and build with -fPIC

--- a/Makefile
+++ b/Makefile
@@ -21,7 +21,7 @@
 # Do not specify CFLAGS or LIBS on the make invocation line - specify
 # XCFLAGS or XLIBS instead. Make ignores any lines in the makefile that
 # set a variable that was set on the command line.
-CFLAGS += $(XCFLAGS) -Iinclude
+CFLAGS += $(XCFLAGS) -Iinclude -fPIC
 LIBS += $(XLIBS) -lm
 
 ifneq ($(threading),no)
@@ -85,7 +85,7 @@
 	$(LINK_CMD)
 
 $(OUT)/%.$(SO):
-	$(LINK_CMD) $(LIB_LDFLAGS) $(THIRD_LIBS) $(LIBCRYPTO_LIBS)
+	$(LINK_CMD) $(LIB_LDFLAGS) -Wl,-soname,$(notdir $@).$(SOVERSION) $(THIRD_LIBS) $(LIBCRYPTO_LIBS)
 
 $(OUT)/%.def: $(OUT)/%.$(SO)
 	$(GENDEF_CMD)
@@ -371,8 +371,12 @@
 
 # --- Update version string header ---
 
-VERSION = $(shell git describe --tags)
+VERSION = $(shell test -d .git \
+	&& git describe --tags 2>/dev/null \
+	|| sed -n 's/.* FZ_VERSION "\([^"]\+\)"/\1/p' include/mupdf/fitz/version.h)
 
+SOVERSION = $(basename $(VERSION))
+
 version:
 	sed -i~ -e '/FZ_VERSION /s/".*"/"'$(VERSION)'"/' include/mupdf/fitz/version.h
 
@@ -410,7 +414,7 @@
 	install -m 644 include/mupdf/pdf/*.h $(DESTDIR)$(incdir)/mupdf/pdf
 ifneq ($(LIBS_TO_INSTALL_IN_LIB),)
 	install -d $(DESTDIR)$(libdir)
-	install -m 644 $(LIBS_TO_INSTALL_IN_LIB) $(DESTDIR)$(libdir)
+	install -m 755 $(LIBS_TO_INSTALL_IN_LIB) $(DESTDIR)$(libdir)
 endif
 
 install-apps: apps