From 9e3e66d37aec942137c3fb241b1983abdbcece7e Mon Sep 17 00:00:00 2001
From: Spencer Russell <sfr@media.mit.edu>
Date: Tue, 9 May 2017 13:08:00 -0400
Subject: [PATCH] now reports hash of source file used to build shim

---
 deps/src/Makefile  | 10 +++++-----
 deps/src/pa_shim.c |  8 ++++----
 src/pa_shim.jl     | 10 +++++++++-
 3 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/deps/src/Makefile b/deps/src/Makefile
index 27aac58..bae0abc 100644
--- a/deps/src/Makefile
+++ b/deps/src/Makefile
@@ -5,13 +5,17 @@ ifeq (exists, $(shell [ -e Make.user ] && echo exists ))
 include Make.user
 endif
 
+TARGETDIR=../usr/lib
+OBJS = pa_shim.o
+SOURCEHASH=$(shell sha256sum pa_shim.c | awk '{print $$1}')
+
 #check-env:
 #ifndef JULIA_INC
 #        $(error Environment variable JULIA_INC is not set.)
 #endif
 
 #INC =-I"$(JULIA_INC)"
-CFLAGS =-Wall -Wno-strict-aliasing -fno-omit-frame-pointer -fPIC -g
+CFLAGS =-Wall -Wno-strict-aliasing -fno-omit-frame-pointer -fPIC -DSOURCEHASH=\"$(SOURCEHASH)\"
 LDFLAGS =-L../../../RingBuffers/deps/usr/lib -lpa_ringbuffer
 # LINUX_LIBS =-lrt
 # LINUX_LDFLAGS =-rdynamic
@@ -19,10 +23,6 @@ LDFLAGS =-L../../../RingBuffers/deps/usr/lib -lpa_ringbuffer
 # portaudio and libsndfile
 # DARWIN_LDFLAGS =-L../../../Homebrew/deps/usr/lib
 # DARWIN_INC =-I../../../Homebrew/deps/usr/include
-TARGETDIR=../usr/lib
-
-OBJS = pa_shim.o
-
 # Figure out OS and architecture
 OS = $(shell uname)
 ifneq (,$(findstring MINGW,$(OS)))
diff --git a/deps/src/pa_shim.c b/deps/src/pa_shim.c
index 1b79708..4317568 100644
--- a/deps/src/pa_shim.c
+++ b/deps/src/pa_shim.c
@@ -3,7 +3,6 @@
 #include <stdio.h>
 #include <unistd.h>
 
-#define SHIM_VERSION 3
 #define MIN(x, y) ((x) < (y) ? (x) : (y))
 
 typedef enum {
@@ -39,10 +38,11 @@ void senderr(pa_shim_info_t *info, pa_shim_errmsg_t msg) {
     }
 }
 
-// return the version of the shim so we can make sure things are in sync
-int pa_shim_getversion(void)
+// return the sha256 hash of the shim source so we can make sure things are in sync
+const char *pa_shim_getsourcehash(void)
 {
-    return SHIM_VERSION;
+    // defined on the command-line at build-time
+    return SOURCEHASH;
 }
 
 /*
diff --git a/src/pa_shim.jl b/src/pa_shim.jl
index 9a97065..040b896 100644
--- a/src/pa_shim.jl
+++ b/src/pa_shim.jl
@@ -29,5 +29,13 @@ mutable struct pa_shim_info_t
     errorhandle::Ptr{Void} # condition to notify on new errors
 end
 
-shimversion() = ccall((:pa_shim_getversion, libpa_shim), Cint, ())
+"""
+    PortAudio.shimhash()
+
+Return the sha256 hash(as a string) of the source file used to build the shim.
+We may use this sometime to verify that the distributed binary stays in sync
+with the rest of the package.
+"""
+shimhash() = unsafe_string(
+        ccall((:pa_shim_getsourcehash, libpa_shim), Cstring, ()))
 Base.unsafe_convert(::Type{Ptr{Void}}, info::pa_shim_info_t) = pointer_from_objref(info)