main: add flags to override config files

Add --aerc-conf, --binds-conf and --accounts-conf CLI flags, which
respectively override the default aerc.conf, binds.conf and
accounts.conf configuration files. If the specified files do not exist
or cannot be read, exit with an error.

Implements: https://todo.sr.ht/~rjarry/aerc/209
Changelog-added: CLI flags to override paths to config files.
Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com>
Acked-by: Robin Jarry <robin@jarry.cc>

4 files changed, 18 insertions, 3 deletions

diff --git a/doc/aerc-accounts.5.scd b/doc/aerc-accounts.5.scd
index 9d95af32..5f89033a 100644
--- a/doc/aerc-accounts.5.scd
+++ b/doc/aerc-accounts.5.scd
@@ -9,7 +9,8 @@ aerc-accounts - account configuration file format for *aerc*(1)
 The _accounts.conf_ file is  used for configuring each mail account used for
 aerc. It is expected to be in your XDG config home plus _aerc_, which defaults
 to _~/.config/aerc/accounts.conf_. This file must be kept secret, as it may
-include your account credentials.
+include your account credentials. An alternate file can be specified via the
+_--accounts-conf_ command line argument, see *aerc*(1).
 
 If _accounts.conf_ does not exist, the *:new-account* configuration wizard will
 be executed automatically on first startup.
diff --git a/doc/aerc-binds.5.scd b/doc/aerc-binds.5.scd
index f9cdd668..b00c12d8 100644
--- a/doc/aerc-binds.5.scd
+++ b/doc/aerc-binds.5.scd
@@ -9,7 +9,8 @@ aerc-binds - key bindings configuration file format for *aerc*(1)
 The _binds.conf_ file is used for configuring keybindings used in the aerc
 interactive client. It is expected to be in your XDG config home plus _aerc_,
 which defaults to _~/.config/aerc/binds.conf_. If the file does not exist, the
-built-in default will be installed.
+built-in default will be installed. An alternate file can be specified via the
+_--binds-conf_ command line argument, see *aerc*(1).
 
 This file is written in the ini format with key bindings defined as:
 
diff --git a/doc/aerc-config.5.scd b/doc/aerc-config.5.scd
index 5acb9427..f3d45085 100644
--- a/doc/aerc-config.5.scd
+++ b/doc/aerc-config.5.scd
@@ -9,7 +9,8 @@ aerc-config - configuration file format for *aerc*(1)
 There are three aerc config files: _aerc.conf_, _binds.conf_, and
 _accounts.conf_. The last one must be kept secret, as it may include your
 account credentials. We look for these files in your XDG config home plus
-_aerc_, which defaults to _~/.config/aerc_.
+_aerc_, which defaults to _~/.config/aerc_. Alternate files can be specified via
+command line arguments, see *aerc*(1).
 
 Examples of these config files are typically included with your installation of
 aerc and are usually installed in _/usr/share/aerc_.
diff --git a/doc/aerc.1.scd b/doc/aerc.1.scd
index ee5b27c5..5be01751 100644
--- a/doc/aerc.1.scd
+++ b/doc/aerc.1.scd
@@ -24,6 +24,18 @@ from your terminal.
 	can also be a comma separated list of names. This option may be
 	specified multiple times. The account order will be preserved.
 
+*--aerc-conf* _</path/to/aerc.conf>_
+	Instead of using _$XDG_CONFIG_HOME/aerc/aerc.conf_ use the file at the
+	specified path for configuring aerc.
+
+*--accounts-conf* _</path/to/accounts.conf>_
+	Instead of using _$XDG_CONFIG_HOME/aerc/accounts.conf_ use the file at the
+	specified path for configuring accounts.
+
+*--binds-conf* _</path/to/binds.conf>_
+	Instead of using _$XDG_CONFIG_HOME/aerc/binds.conf_ use the file at the
+	specified path for configuring binds.
+
 *mailto:*_address[,address][?query[&query]]_
 	Open the composer with the address(es) in the To field. These
 	addresses must not be percent encoded.