Allow a cppcheck check_level to be specified

Version 2.14.0 of cppcheck generates errors relating to the
check level (e.g.):-

    common/base64.c:0:0: information: Limiting analysis of branches. Use --check-level=exhaustive to analyze all branches. [normalCheckLevelMaxBranches]

This does not happen with the same sources (commit
f781962a55) under 2.13.0.

This PR disables the warnings above for 2.14.0, but also allows a '-f'
argument to be passed in to request an exhaustive test. This could be used
(for example) before a major release. An exhaustive test takes a *lot*
longer. The first run with a git runner was around an hour.

The --check-level=flag was only added for 2.11.0, and so this now needs
a version check.

scripts/run_cppcheck.sh

@@ -2,9 +2,11 @@
 
 # Script to run cppcheck
 #
-# Usage: /path/to/run_cppcheck.sh [ -v CPPCHECK_VER] [<extra_opts_and_dirs>]
+# Usage: /path/to/run_cppcheck.sh [-f] [ -v CPPCHECK_VER] [<extra_opts_and_dirs>]
 #
 # - If <extra_opts_and_dirs> is missing, '.' is assumed
+# - If '-f' is specified, the exhaustive check level is used. This can take
+#   an hour or two.
 # - If -v CPPCHECK_VER is specified, that version of cppcheck is run from
 #   ~/cppcheck.local (whether or not it's there!). Use install_cppcheck.sh
 #   to install a new version.
@@ -14,11 +16,50 @@
 # CPPCHECK       : Override the default cppcheck command ('cppcheck').
 #                  Ignored if -v is specified
 # CPPCHECK_FLAGS : Override the default cppcheck flags
+# CPPCHECK_QUICK : If non-zero, disables the exhaustive check level.
+#                  Useful when developing
+
+# ----------------------------------------------------------------------------
+# C P P C H E C K   V E R S I O N   S T R
+#
+# Get the cppcheck version, and then convert to AABBCC for comparisons
+# where AA is the major version, BB is the minor version and CC is the
+# revision
+# For example, cppcheck version 2.13.0 produces 021300
+# ----------------------------------------------------------------------------
+CppcheckVerCompareStr()
+{
+    # shellcheck disable=SC2046
+    set -- $($CPPCHECK --version 2>/dev/null)
+    while [ $# -gt 0 ]; do
+        case "$1" in
+            [0123456789]*) break;;
+            *) shift
+        esac
+    done
+
+    if [ $# -eq 0 ]; then
+        echo 000000 ; # Something has gone wrong
+    else
+        case "$1" in
+            *.*.*) echo "$1" | awk -F.  '{printf "%02d%02d%02d",$1,$2,$3 }' ;;
+            *.*)   echo "$1" | awk -F.  '{printf "%02d%02d00",$1,$2 }' ;;
+            *)     printf '%02d0000\n' "$1"
+        esac
+    fi
+}
 
 INSTALL_ROOT=~/cppcheck.local
 
-# Figure out CPPCHECK setting, if any. Currently '-v' must be the first
-# argument on the command line.
+# Exhaustive test?
+if [ "$1" = "-f" ]; then
+    check_level=exhaustive
+    shift
+else
+    check_level=normal
+fi
+
+# Figure out CPPCHECK setting, if any.
 case "$1" in
     -v) # Version is separate parameter
         if [ $# -ge 2 ]; then
@@ -45,15 +86,30 @@ if [ -z "$CPPCHECK_FLAGS" ]; then
     CPPCHECK_FLAGS="--quiet --force --std=c11 --std=c++11 --inline-suppr \
                     --enable=warning --error-exitcode=1 -i third_party \
                     --suppress=uninitMemberVar:ulalaca/ulalaca.cpp \
-                    --suppress=shiftTooManyBits:libxrdp/xrdp_mppc_enc.c \
-                    -I . -I common"
+                    --suppress=shiftTooManyBits:libxrdp/xrdp_mppc_enc.c"
+
+    # Check for flags added in later versions
+    CPPCHECK_COMPARE_VERSION=$(CppcheckVerCompareStr)
+    if [ "$CPPCHECK_COMPARE_VERSION" -ge 021100 ]; then
+        if [ "$check_level" = "normal" ]; then
+            # Disable warnings related to the check level
+            CPPCHECK_FLAGS="$CPPCHECK_FLAGS \
+                --suppress=normalCheckLevelMaxBranches"
+        fi
+        CPPCHECK_FLAGS="$CPPCHECK_FLAGS --check-level=$check_level"
+    else
+        # This is echoed later
+        check_level="Default (option not supported)"
+    fi
+
+    CPPCHECK_FLAGS="$CPPCHECK_FLAGS -I . -I common"
 fi
 CPPCHECK_FLAGS="$CPPCHECK_FLAGS -D__cppcheck__"
 
 # Any options/directories specified?
 if [ $# -eq 0 ]; then
     if [ -f /proc/cpuinfo ]; then
-        cpus=$(grep '^processor' /proc/cpuinfo | wc -l)
+        cpus=$(grep -c '^processor' /proc/cpuinfo)
     else
         cpus=2
     fi
@@ -63,5 +119,8 @@ fi
 # Display the cppcheck version and command for debugging
 "$CPPCHECK" --version && {
     echo "Command: $CPPCHECK $CPPCHECK_FLAGS" "$@"
+    echo "Check level: $check_level"
+
+    # shellcheck disable=SC2086
     "$CPPCHECK" $CPPCHECK_FLAGS "$@"
 }