[pacman-dev] [PATCH 6/6] pacman-key: fix parsing of command line options

[ivan.kanak at gmail.com]

From: Ivan Kanakarakis <ivan.kanak at gmail.com>

This commit fixes handling of --help/-h --version/-V options. Previously
$ pacman-key --help
would return errors if the configuration file was missing or the user
did not have root privileges. Same was for --version switch.
Moreover this fixes a bug that caused the command line specified
gpgdir (PACMAN_KEYRING_DIR) to be overridden by the values from the
configuration file.

The parsing now happens as follows:
a. The script parses --config and/or --gpgdir if those are specified.
These options should be the first arguments given to the script.
b. The script reads the first command, that is the first argument after
the --config and/or --gpgdir parsing is done.
If no command was provided the script exits with an error.
If the command is one of --help -h --version -V then it skip the checks
that would otherwise be needed, executes those and exits.
If the command is other, the script checks by order:
  - the dependencies are met (currently existence of gpg executable)
  - the user has root privileges
  - the configuration file is readable
  - the gpgdir is set and exists
c. If all checks pass the command is matched to a case and the
appropriate set of commands is executed.

Signed-off-by: Ivan Kanakarakis <ivan.kanak at gmail.com>
---
 scripts/pacman-key.sh.in |   69 ++++++++++++++++++++++++++--------------------
 1 files changed, 39 insertions(+), 30 deletions(-)

diff --git a/scripts/pacman-key.sh.in b/scripts/pacman-key.sh.in
index b5fca2b..5a07784 100644
--- a/scripts/pacman-key.sh.in
+++ b/scripts/pacman-key.sh.in
@@ -217,20 +217,11 @@ if ! type gettext &>/dev/null; then
 	}
 fi
 
-if [[ $1 != "--version" && $1 != "-V" && $1 != "--help" && $1 != "-h" && $1 != "" ]]; then
-	if ! type -p gpg &>/dev/null; then
-		error "$(gettext "gnupg does not seem to be installed.")"
-		msg2 "$(gettext "pacman-key requires gnupg for most operations.")"
-		exit 1
-	elif (( EUID != 0 )); then
-		error "$(gettext "pacman-key needs to be run as root.")"
-		exit 1
-	fi
-fi
+# Set default values
+CONFIG_DEF="@sysconfdir@/pacman.conf"
+PACMAN_KEYRING_DIR_DEF="@sysconfdir@/pacman.d/gnupg"
 
-# Parse global options
-CONFIG="@sysconfdir@/pacman.conf"
-PACMAN_KEYRING_DIR="@sysconfdir@/pacman.d/gnupg"
+# Parse command line options
 while [[ $1 =~ ^--(config|gpgdir)$ ]]; do
 	case "$1" in
 		--config) shift; CONFIG="$1" ;;
@@ -239,23 +230,7 @@ while [[ $1 =~ ^--(config|gpgdir)$ ]]; do
 	shift
 done
 
-if [[ ! -r "${CONFIG}" ]]; then
-	error "$(gettext "%s not found.")" "$CONFIG"
-	exit 1
-fi
-
-# Read GPGDIR from $CONFIG.
-if [[ GPGDIR="$(get_from "$CONFIG" "GPGDir")" == 0 ]]; then
-	PACMAN_KEYRING_DIR="${GPGDIR}"
-fi
-GPG_PACMAN="gpg --homedir ${PACMAN_KEYRING_DIR} --no-permission-warning"
-
-# Try to create $PACMAN_KEYRING_DIR if non-existent
-# Check for simple existence rather than for a directory as someone may want
-# to use a symlink here
-[[ -e ${PACMAN_KEYRING_DIR} ]] || mkdir -p -m 755 "${PACMAN_KEYRING_DIR}"
-
-# Parse and execute command
+# Parse the command
 command="$1"
 if [[ -z "${command}" ]]; then
 	usage
@@ -263,6 +238,40 @@ if [[ -z "${command}" ]]; then
 fi
 shift
 
+# If command is --help/-h or --version/-V then skip checks and execute those
+if [[ ! ${command} =~ ^(--help|-h|--version|-V)$ ]]; then
+    # check dependencies
+    if ! type -p gpg &>/dev/null; then
+         error "$(gettext "gnupg does not seem to be installed.")"
+         msg2 "$(gettext "pacman-key requires gnupg for most operations.")"
+         exit 1
+    fi
+    # check permissions
+    if (( ! EUID )); then
+        error "$(gettext "pacman-key needs to be run as root.")"
+        exit 1
+    fi
+    # Use the default CONFIG if the user didn't specify one
+    [[ -z $CONFIG ]] && CONFIG="$CONFIG_DEF"
+    # If configuration file is not readable exit with error message
+    if [[ ! -r $CONFIG ]]; then
+        error "$(gettext "unreadable configuration file: %s")" "$CONFIG"
+        exit 1
+    fi
+    # if the user didn't specify PACMAN_KEYRING_DIR
+    # then read GPGDir from the configuration file
+    [[ -z $PACMAN_KEYRING_DIR ]] && PACMAN_KEYRING_DIR="$(get_from "$CONFIG" "GPGDir")"
+    # if no such setting exists, use the default value
+    [[ -z $PACMAN_KEYRING_DIR ]] && PACMAN_KEYRING_DIR="$PACMAN_KEYRING_DIR_DEF"
+    # Try to create $PACMAN_KEYRING_DIR if non-existent
+    # Check for simple existence rather than a directory
+    # as someone may want to use a symlink here
+    [[ ! -e ${PACMAN_KEYRING_DIR} ]] && mkdir -p -m 755 "${PACMAN_KEYRING_DIR}"
+fi
+
+GPG_PACMAN="gpg --homedir ${PACMAN_KEYRING_DIR} --no-permission-warning"
+
+# Execute the command
 case "${command}" in
 	-a|--add)
 		# If there is no extra parameter, gpg will read stdin
-- 
1.7.4.4