Allow out-of-vcs builds

HACKING.BUILD.md

@@ -11,6 +11,7 @@ This list was previously maintained as [issue #242](https://github.com/majn/tele
 1. Any changes due to `make -C tgl` must cause all necessary rebuilds in telegram-purple during the same invocation of make. ("Too often" is acceptable as long as `make && make` isn't violated.)
 1. If `tgl/Makefile.in` is missing, explain that we need submodules, and stop.
 1. `make -j12` must work fine
+1. Must support out-of-CVS builds.
 
 ## While ensuring that:
 
@@ -20,12 +21,13 @@ This list was previously maintained as [issue #242](https://github.com/majn/tele
 
 ## Approach:
 
-- `commit.h` is a regular file which depends on a .PHONY target `commit`. Building `commit.h` *only* touches `commit.h` if necessary. (=> 1 & 2)
+- `commit.h` is a regular file which depends on a .PHONY target `commit`. Building `commit.h` *only* touches `commit.h` if necessary and possible. (=> 1, 2, half of 8)
 - Have a target `tgl/Makefile` which depends on `Makefile`. (=> 3)
 - The central target `${PRPL_LIBNAME}` shall depend on the .PHONY `submade`, which depends on `tgl/Makefile`, and essentially executes `make -C tgl`. (=> 4, time constraint of 5)
 - All objects of telegram-purple depend on `tgl/libs/libtgl.a`. Rationale: if `tgl/libs/libtgl.a` stays the same, then nothing in tgl changed. If `tgl/libs/libtgl.a` changes, then due to lots of black preprocessor magic within tgl, it can't be safely determined which, if any, objects of telegram-purple can be re-used. Also, if tgl got recompiled (~ 1 minute), then tgp can be recompiled, too (~ 5 seconds). (=> dependency constraint of 5)
 - Let `tgl/Makefile` depend on `tgl/Makefile.in`, and put the warning into the rule for the latter. (=> 6)
 - The above already implies a dependency DAG that is completely known to make; except at one point: let `tgl/libs/libtgl.a` depend on `submade`, without any own code. Now make ensure thread-safety on it's own. (=> 7)
+- Bundle commit.h into the origtar (=> other half of 8)
 
 ## Side effects:
 

Makefile.in

@@ -215,7 +215,7 @@ check-clean: .git
 
 # Feel free to remove the "check-clean" dependency if you know what you're doing.
 .PHONY: dist
-dist: check-clean .git create_dirs
+dist: check-clean commit.h .git create_dirs
 	./gen-origtar
 
 

commit.h.gen

@@ -20,6 +20,18 @@
 
 set -e
 
+if ! (command -v git && git status) >/dev/null 2>&1
+then
+  if test -r commit.h
+  then
+    echo "No git available. Assuming everything is up-to-date."
+    exit 0
+  else
+    echo >&2 "No git available. Can't reconstruct commit.h"
+    exit 1
+  fi
+fi
+
 GIT_COMMIT=`git rev-parse HEAD | cut -c1-10`
 
 if grep -scq "${GIT_COMMIT}" commit.h

gen-origtar

@@ -21,17 +21,26 @@
 set -e
 
 # -- Cleanup possibly left-over artifacts
-rm -f bin/tgl_tl-parser.tar bin/tgl.tar bin/result.tar bin/result.tar.gz
+rm -f bin/tgl_tl-parser.tar bin/tgl.tar bin/commit.h.tar bin/result.tar bin/result.tar.gz
 
 # -- Create parts
 # Abuse the "bin" dir for temporary files.
 ( cd tgl/tl-parser && git archive --prefix=telegram-purple/tgl/tl-parser/ --output=../../bin/tgl_tl-parser.tar HEAD )
 ( cd tgl && git archive --prefix=telegram-purple/tgl/ --output=../bin/tgl.tar HEAD )
 git archive --prefix=telegram-purple/ --output=bin/result.tar HEAD
+# This is a lot of options. Here's why.
+# --sort --mtime --owner --group => be reproducible (same commit produces binarily identical files)
+# --transform                    => be in the same "tar-folder" as the rest
+# (absence of --numeric-ids)     => have identical behavior as git-archive
+# --mode=664                     => have identical behavior as git-archive
+#                                   http://www.gelato.unsw.edu.au/archives/git/0701/36326.html
+#                                   This is hacky. TODO: Find a better way to unify permissions.
+tar --sort=name --mtime="1970-01-01 00:00Z" --owner=root --group=root --transform s%^%telegram-purple/% --mode=664 -cf bin/commit.h.tar commit.h
 
 # -- Concatenate it all
 tar --concatenate -f bin/result.tar bin/tgl.tar
 tar --concatenate -f bin/result.tar bin/tgl_tl-parser.tar
+tar --concatenate -f bin/result.tar bin/commit.h.tar
 gzip -n bin/result.tar
 
 # -- Determine name and move
@@ -41,4 +50,4 @@ echo mv -f bin/result.tar.gz $TARNAME
 mv -f bin/result.tar.gz $TARNAME
 
 # -- Cleanup (never fail)
-rm -f bin/tgl_tl-parser.tar bin/tgl.tar bin/result.tar bin/result.tar.gz || true
+rm -f bin/tgl_tl-parser.tar bin/tgl.tar bin/commit.h.tar bin/result.tar bin/result.tar.gz || true