pre-commit: Avoid launching python subprocesses.

This makes Python required only for (portable) fnmatch().

Change the ignore script to work as a filter.

Multi-platform improvements.

Change-Id: I6ac757d48ba2ff965da5da3dc9c25047a0e37f92
Reviewed-on: https://code.wireshark.org/review/13693
Reviewed-by: Michael Mann <mmann78@netscape.net>
Reviewed-by: João Valverde <j@v6e.pt>

4 files changed, 63 insertions, 53 deletions

diff --git a/tools/Makefile.am b/tools/Makefile.am
index 60e04065a4..c70b7f4f6c 100644
--- a/tools/Makefile.am
+++ b/tools/Makefile.am
@@ -169,6 +169,8 @@ EXTRA_DIST = \
 	parse_xml2skinny_dissector.py			\
 	pkt-from-core.py				\
 	pre-commit					\
+	pre-commit-ignore.conf				\
+	pre-commit-ignore.py				\
 	process-x11-fields.pl				\
 	process-x11-xcb.pl				\
 	randpkt-test.sh					\
diff --git a/tools/pre-commit b/tools/pre-commit
index 796eb5e4ee..14f3cd2156 100755
--- a/tools/pre-commit
+++ b/tools/pre-commit
@@ -19,12 +19,22 @@
 # If the commit identifier is not given, use HEAD instead.
 COMMIT_ID="${1:-HEAD}"
 
+UNAME=`uname -o`
+
+case "$UNAME" in
+    Msys)
+        pyvar="pythonw.exe"
+        ;;
+    *)
+        pyvar="python"
+        ;;
+esac
+
+PYBIN=${WS_GITHOOK_PYTHON:-$pyvar}
+
 # Path to hook script in the .git directory
 hook_script=${GIT_DIR:-.git}/hooks/pre-commit
 
-# Path to check script in the tools directory
-check_script=./tools/pre-commit-check.py
-
 # Always start in the root directory of the source tree, this allows for
 # invocations via relative paths (such as ../tools/pre-commit):
 cd "$(git rev-parse --show-toplevel)"
@@ -37,14 +47,41 @@ fi
 
 exit_status=0
 
-if [ -e "$check_script" ]
-then
-    python "$check_script" ${COMMIT_ID} || exit_status=1
-else
-    echo "File '$check_script' not found. Aborting."
+COMMIT_FILES=`git diff-index --cached --name-status ${COMMIT_ID} | grep -v "^D" | cut -f2 | grep "\.[ch]$"`
+
+# Path to filter script in the tools directory
+filter_script=${PWD}/tools/pre-commit-ignore.py
+filter_conf=${PWD}/tools/pre-commit-ignore.conf
+
+if [ ! -e "$filter_script" ]; then
+    echo "File '$filter_script' does not exist. Aborting."
+    exit 1
+fi
+
+CHECK_FILES=`echo "$COMMIT_FILES" | "$PYBIN" "$filter_script" "$filter_conf"`
+if [ $? -ne 0 ]; then
     exit 1
 fi
 
+# On windows python will output \r\n line endings - we don't want that
+CHECK_FILES=`echo "$CHECK_FILES" | sed 's/\r//g'`
+
+for FILE in $CHECK_FILES; do
+
+    #Check if checkhf is good
+    ./tools/checkhf.pl $FILE            || exit_status=1
+
+    #Check if checkAPIs is good
+    ./tools/checkAPIs.pl -p $FILE       || exit_status=1
+
+    #Check if fix-encoding-args is good
+    ./tools/fix-encoding-args.pl $FILE  || exit_status=1
+
+    #Check if checkfiltername is good
+    ./tools/checkfiltername.pl $FILE    || exit_status=1
+
+done
+
 # If there are whitespace errors, print the offending file names and fail. (from git pre-commit.sample)
 git diff-index --check --cached ${COMMIT_ID}    || exit_status=1
 
diff --git a/tools/pre-commit-check.conf b/tools/pre-commit-ignore.conf
index f3eebc58f3..6c79168e41 100644
--- a/tools/pre-commit-check.conf
+++ b/tools/pre-commit-ignore.conf
@@ -4,7 +4,7 @@
 # Each line is compared against the output of 'git diff-index --name-only'.
 # For example to skip checking this file add:
 #
-# tools/pre-commit-check.conf
+# tools/pre-commit-ignore.conf
 #
 # The pathname wildcards allowed are: '*', '?', character set '[abc]' or
 # negated with '[!abc]'.
diff --git a/tools/pre-commit-check.py b/tools/pre-commit-ignore.py
index fa66e1b439..d043368a95 100755
--- a/tools/pre-commit-check.py
+++ b/tools/pre-commit-ignore.py
@@ -20,24 +20,18 @@
 
 import sys
 import os
-import re
 import fnmatch
-import filecmp
 
-TOOLS_DIR = "tools"
-CHECK_CONF = "pre-commit-check.conf"
-
-CHECK_LIST = ["checkhf.pl", "checkAPIs.pl -p", "fix-encoding-args.pl", "checkfiltername.pl"]
+IGNORE_CONF = "pre-commit-ignore.conf"
 
 if len(sys.argv) > 2:
-    print("Usage: {0} [COMMIT]".format(sys.argv[0]))
+    print("Usage: {0} [path/to/ignore.conf]".format(sys.argv[0]))
     sys.exit(1)
 
-# If the commit identifier is not given, use HEAD instead.
 if len(sys.argv) == 2:
-    COMMIT_ID = sys.argv[1]
+    ignore_path = sys.argv[1]
 else:
-    COMMIT_ID = "HEAD"
+    ignore_path = IGNORE_CONF
 
 # Function to load our patterns from 'path' for modified files
 # to be ignored (skipping any comments)
@@ -46,47 +40,24 @@ def load_checkignore(path):
         with open(path) as f:
             patterns = f.read()
     except OSError as err:
-        print("'" + path + "':", str(err))
+        print(str(err))
         return []
     ign = [l.strip() for l in patterns.splitlines()]
     ign = [l for l in ign if l and not l.startswith("#")]
     return ign
 
-IGNORE_LIST = load_checkignore(os.path.join(TOOLS_DIR, CHECK_CONF))
-
-# Run git-diff index and process/filter output
-def run_diff_index():
-    ret = []
-    with os.popen("git diff-index --cached --name-status " + COMMIT_ID) as p:
-        diff = p.read()
-    for l in diff.splitlines():
-        l = l.lstrip()
-        if l.startswith("D"):
-            continue
-        l = l.split()
-        f = l[1].strip()
-        if not re.search("\.[ch]$", f):
-            continue
-        for pattern in IGNORE_LIST:
-            if fnmatch.fnmatchcase(f, pattern):
-                f = None
-                break
-        if f:
-            ret.append(f)
-    return ret
-
-exit_status = 0
+ignore_list = load_checkignore(ignore_path)
 
-# For each valid modified file run our checks
-for f in run_diff_index():
-    for c in CHECK_LIST:
-        script = os.path.join(TOOLS_DIR, c)
-        cmd = "perl {0} {1}".format(script, f)
-        ret = os.system(cmd)
-        if ret != 0:
-            exit_status = 1
+def ignore_match(f):
+    for p in ignore_list:
+        if fnmatch.fnmatchcase(f, p):
+            return True
+    return False
 
-sys.exit(exit_status)
+for line in sys.stdin:
+    line = line.strip()
+    if not ignore_match(line):
+        print(line)
 
 #
 #  Editor modelines