Fix #130 don't export private symbols.

In CMakeLists.txt use cmake's GenerateExportHeader support to generate
src/librsync_export.h and add it as a header to install. Set
"C_VISIBILITY_PRESET hidden" target property for rsync to hide all
not-explicitly-exported symbols. Do some minor indent tidying.

Add librsync_export.h to .gitignore and remove obsolete
librsync-config.h.

In librsync.h include librsync_export.h and explicitly export all
functions. Ensure it is correctly formated using "make tidyc".

In rdiff.c remove all includes and references to anything not
explicitly exported by librsync. This included usage of not exported
logging functions rs_error() and rs_log(). Update rdiff_usage() to
support formatted args with nicer output and use it everywhere we
report bad arguments instead of rs_error(). Always use exit() instead
of return for syntax errors to give neater termination output. Remove
PROGRAM define and just use "rdiff" instead.

In fileutil.[hc] move declarations for rs_file_open() and
rs_file_close() to librsync.h and explicitly export them. They are
used by rdiff.

In sumset.h move declaration of rs_signature_log_stats() to
librsync.h, and explicitly export it. It is used by rdiff.

In delta.c explicitly export rs_roll_paranoia and add it as an extern
in librsync.h. This is used by rdiff.

In sumset.c explicitly export RS_MD4_SUM_LENGTH and
RS_BLAKE2_SUM_LENGTH which are extern consts in librsync.h.

In whole.c explicitly export rs_inbuflen and rs_outbuflen which are
extern vars in librsync.h.

In version.c explicitly export rs_librsync_version which is an extern
const in librsync.h.

1 files changed, 1 insertions, 1 deletions

diff --git a/.gitignore b/.gitignore
index 6c7ef2a..8b09f72 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,7 +4,7 @@ CMakeCache.txt
 CTestTestfile.cmake
 config.h
 *.cbp
-librsync-config.h
+librsync_export.h
 librsync.so*
 librsync.a
 librsync*.dylib