1 files changed, 149 insertions, 0 deletions
diff --git a/scripts/Dependencies.py b/scripts/Dependencies.py
new file mode 100644
index 000000000..86a2d3b22
--- /dev/null
+++ b/scripts/Dependencies.py
@@ -0,0 +1,149 @@
+#!/usr/bin/env python
+# Dependencies.py - discover, read, and write dependencies file for make.
+# The format like the output from "g++ -MM" which produces a
+# list of header (.h) files used by source files (.cxx).
+# As a module, provides
+#	FindPathToHeader(header, includePath) -> path
+#	FindHeadersInFile(filePath) -> [headers]
+#	FindHeadersInFileRecursive(filePath, includePath, renames) -> [paths]
+#	FindDependencies(sourceGlobs, includePath, objExt, startDirectory, renames) -> [dependencies]
+#	ExtractDependencies(input) -> [dependencies]
+#	TextFromDependencies(dependencies)
+#	WriteDependencies(output, dependencies)
+#	UpdateDependencies(filepath, dependencies)
+#	PathStem(p) -> stem
+#	InsertSynonym(dependencies, current, additional) -> [dependencies]
+# If run as a script reads from stdin and writes to stdout.
+# Only tested with ASCII file names.
+# Copyright 2019 by Neil Hodgson <neilh@scintilla.org>
+# The License.txt file describes the conditions under which this software may be distributed.
+# Requires Python 2.7 or later
+
+import codecs, glob, os, sys
+
+from . import FileGenerator
+
+continuationLineEnd = " \\"
+
+def FindPathToHeader(header, includePath):
+	for incDir in includePath:
+		relPath = os.path.join(incDir, header)
+		if os.path.exists(relPath):
+			return relPath
+	return ""
+
+fhifCache = {}	# Remember the includes in each file. ~5x speed up.
+def FindHeadersInFile(filePath):
+	if filePath not in fhifCache:
+		headers = []
+		with codecs.open(filePath, "r", "utf-8") as f:
+			for line in f:
+				if line.strip().startswith("#include"):
+					parts = line.split()
+					if len(parts) > 1:
+						header = parts[1]
+						if header[0] != '<':	# No system headers
+							headers.append(header.strip('"'))
+		fhifCache[filePath] = headers
+	return fhifCache[filePath]
+
+def FindHeadersInFileRecursive(filePath, includePath, renames):
+	headerPaths = []
+	for header in FindHeadersInFile(filePath):
+		if header in renames:
+			header = renames[header]
+		relPath = FindPathToHeader(header, includePath)
+		if relPath and relPath not in headerPaths:
+				headerPaths.append(relPath)
+				subHeaders = FindHeadersInFileRecursive(relPath, includePath, renames)
+				headerPaths.extend(sh for sh in subHeaders if sh not in headerPaths)
+	return headerPaths
+
+def RemoveStart(relPath, start):
+	if relPath.startswith(start):
+		return relPath[len(start):]
+	return relPath
+
+def ciKey(f):
+	return f.lower()
+
+def FindDependencies(sourceGlobs, includePath, objExt, startDirectory, renames={}):
+	deps = []
+	for sourceGlob in sourceGlobs:
+		sourceFiles = glob.glob(sourceGlob)
+		# Sorting the files minimizes deltas as order returned by OS may be arbitrary
+		sourceFiles.sort(key=ciKey)
+		for sourceName in sourceFiles:
+			objName = os.path.splitext(os.path.basename(sourceName))[0]+objExt
+			headerPaths = FindHeadersInFileRecursive(sourceName, includePath, renames)
+			depsForSource = [sourceName] + headerPaths
+			depsToAppend = [RemoveStart(fn.replace("\\", "/"), startDirectory) for
+				fn in depsForSource]
+			deps.append([objName, depsToAppend])
+	return deps
+
+def PathStem(p):
+	""" Return the stem of a filename: "CallTip.o" -> "CallTip" """
+	return os.path.splitext(os.path.basename(p))[0]
+
+def InsertSynonym(dependencies, current, additional):
+	""" Insert a copy of one object file with dependencies under a different name.
+	Used when one source file is used to create two object files with different
+	preprocessor definitions. """
+	result = []
+	for dep in dependencies:
+		result.append(dep)
+		if (dep[0] == current):
+			depAdd = [additional, dep[1]]
+			result.append(depAdd)
+	return result
+
+def ExtractDependencies(input):
+	""" Create a list of dependencies from input list of lines
+	Each element contains the name of the object and a list of
+	files that it depends on.
+	Dependencies that contain "/usr/" are removed as they are system headers. """
+
+	deps = []
+	for line in input:
+		headersLine = line.startswith(" ") or line.startswith("\t")
+		line = line.strip()
+		isContinued = line.endswith("\\")
+		line = line.rstrip("\\ ")
+		fileNames = line.strip().split(" ")
+		if not headersLine:
+			# its a source file line, there may be headers too
+			sourceLine = fileNames[0].rstrip(":")
+			fileNames = fileNames[1:]
+			deps.append([sourceLine, []])
+		deps[-1][1].extend(header for header in fileNames if "/usr/" not in header)
+	return deps
+
+def TextFromDependencies(dependencies):
+	""" Convert a list of dependencies to text. """
+	text = ""
+	indentHeaders = "\t"
+	joinHeaders = continuationLineEnd + "\n" + indentHeaders
+	for dep in dependencies:
+		object, headers = dep
+		text += object + ":"
+		for header in headers:
+			text += joinHeaders
+			text += header
+		if headers:
+			text += "\n"
+	return text
+
+def UpdateDependencies(filepath, dependencies, comment=""):
+	""" Write a dependencies file if different from dependencies. """
+	FileGenerator.UpdateFile(filepath, comment+TextFromDependencies(dependencies))
+
+def WriteDependencies(output, dependencies):
+	""" Write a list of dependencies out to a stream. """
+	output.write(TextFromDependencies(dependencies))
+
+if __name__ == "__main__":
+	""" Act as a filter that reformats input dependencies to one per line. """
+	inputLines = sys.stdin.readlines()
+	deps = ExtractDependencies(inputLines)
+	WriteDependencies(sys.stdout, deps)