Make user tigrc location configurable

Introduces the variable TIG_USER_CONFIG which defaults to `~/.tigrc`.

Closes #479

INSTALL.adoc

@@ -88,6 +88,7 @@ can be one of the following flags:
  - `NO_BUILTIN_TIGRC`: Reduce the size of the binary by not including a
    built-in tigrc. The built-in tigrc is used as a fallback when no
    `tigrc` is found in the system configuration directory (e.g. `/etc`).
+ - `TIG_USER_CONFIG`: Allow to customize the `tigrc` path (default `~/.tigrc`).
 
 The following example `config.make` manually configures Tig to use the ncurses
 library with wide character support and include the proper ncurses header file

Makefile

@@ -63,6 +63,9 @@ endif
 
 override CPPFLAGS += '-DTIG_VERSION="$(VERSION)"'
 override CPPFLAGS += '-DSYSCONFDIR="$(sysconfdir)"'
+ifdef TIG_USER_CONFIG
+override CPPFLAGS += '-DTIG_USER_CONFIG="$(TIG_USER_CONFIG)"'
+endif
 
 ASCIIDOC ?= asciidoc
 ASCIIDOC_FLAGS = -aversion=$(VERSION) -asysconfdir=$(sysconfdir) -f doc/asciidoc.conf

NEWS.adoc

@@ -30,6 +30,7 @@ Improvements:
  - Add sample git-flow keybinding (GH #421)
  - Add chocolate theme (GH #432)
  - Show stash diffs. (GH #328)
+ - Make user tigrc location configurable. (GH #479)
 
 Bug fixes:
 

include/tig/options.h

@@ -26,6 +26,10 @@ struct ref_format;
 struct view_column;
 typedef struct view_column *view_settings;
 
+#ifndef TIG_USER_CONFIG
+#define TIG_USER_CONFIG "~/.tigrc"
+#endif
+
 #define OPTION_INFO(_) \
 	_(blame_options,		const char **,		VIEW_BLAME_LIKE) \
 	_(blame_view,			view_settings,		VIEW_NO_FLAGS) \

src/options.c

@@ -947,7 +947,7 @@ load_options(void)
 	}
 
 	if (!tigrc_user)
-		tigrc_user = "~/.tigrc";
+		tigrc_user = TIG_USER_CONFIG;
 	load_option_file(tigrc_user);
 
 	if (!diff_opts_from_args && tig_diff_opts && *tig_diff_opts) {