main,win32: introduce an option replacing backslashes in input file names with slashes

(TODO: documentation, more log should be here)

Suggested by @k-takata in #1325.

Author: masatake

Tmain/option-use-slash-as-filename-separator.d/run.sh

@@ -0,0 +1,26 @@
+# Copyright: 2019 Masatake YAMATO
+# License: GPL-2
+
+CTAGS=$1
+OPT=--use-slash-as-filename-separator
+
+. ../utils.sh
+
+exit_unless_win32 $CTAGS
+
+echo '#u-ctags output'
+$CTAGS --quiet --options=NONE -o -      'src\input.c'
+$CTAGS --quiet --options=NONE -o - $OPT 'src\input.c'
+$CTAGS --quiet --options=NONE -o - ${OPT}=no 'src\input.c'
+
+echo '#e-ctags output'
+$CTAGS --quiet --options=NONE --output-format=e-ctags -o -           'src\input.c'
+$CTAGS --quiet --options=NONE --output-format=e-ctags -o - $OPT      'src\input.c'
+$CTAGS --quiet --options=NONE --output-format=e-ctags -o - ${OPT}=no 'src\input.c'
+
+echo '#xref output'
+$CTAGS --quiet --options=NONE --output-format=xref -o -           'src\input.c'
+$CTAGS --quiet --options=NONE --output-format=xref -o - $OPT      'src\input.c'
+$CTAGS --quiet --options=NONE --output-format=xref -o - ${OPT}=no 'src\input.c'
+
+# TODO: json output

Tmain/option-use-slash-as-filename-separator.d/src/input.c

@@ -0,0 +1 @@
+int n;

Tmain/option-use-slash-as-filename-separator.d/stdout-expected.txt

@@ -0,0 +1,12 @@
+#u-ctags output
+n	src/input.c	/^int n;$/;"	v	typeref:typename:int
+n	src/input.c	/^int n;$/;"	v	typeref:typename:int
+n	src\\input.c	/^int n;$/;"	v	typeref:typename:int
+#e-ctags output
+n	src\input.c	/^int n;$/;"	v	typeref:typename:int
+n	src/input.c	/^int n;$/;"	v	typeref:typename:int
+n	src\input.c	/^int n;$/;"	v	typeref:typename:int
+#xref output
+n                variable      1 src\\input.c      int n;
+n                variable      1 src/input.c      int n;
+n                variable      1 src\\input.c      int n;

main/entry.c

@@ -1236,6 +1236,20 @@ static void writeTagEntry (const tagEntryInfo *const tag, bool checkingNeeded)
 
 	DebugStatement ( debugEntry (tag); )
 
+#ifdef WIN32
+	if (Option.useSlashAsFilenameSeparator == FILENAME_SEP_USE_SLASH)
+	{
+		Assert (((const tagEntryInfo *)tag)->inputFileName);
+		char *c = (char *)(((tagEntryInfo *const)tag)->inputFileName);
+		while (*c)
+		{
+			if (*c == PATH_SEPARATOR)
+				*c = OUTPUT_PATH_SEPARATOR;
+			c++;
+		}
+	}
+#endif
+
 	if (includeExtensionFlags ()
 	    && isXtagEnabled (XTAG_QUALIFIED_TAGS)
 	    && doesInputLanguageRequestAutomaticFQTag ()

main/options.c

@@ -172,6 +172,9 @@ optionValues Option = {
 	.putFieldPrefix = false,
 	.maxRecursionDepth = 0xffffffff,
 	.interactive = false,
+#ifdef WIN32
+	.useSlashAsFilenameSeparator = FILENAME_SEP_UNSET,
+#endif
 #ifdef DEBUG
 	.breakLine = 0,
 #endif
@@ -416,6 +419,10 @@ static optionDescription LongOptionDescription [] = {
  {0,"       never:  be absolute even if input files are passed in with relative paths" },
  {1,"  --totals=[yes|no|extra]"},
  {1,"       Print statistics about input and tag files [no]."},
+#ifdef WIN32
+ {1,"  --use-slash-as-filename-separator"},
+ {1,"       Use slash as filename separator [no]."},
+#endif
  {1,"  --verbose=[yes|no]"},
  {1,"       Enable verbose messages describing actions on each input file."},
  {1,"  --version"},
@@ -2786,6 +2793,9 @@ static booleanOption BooleanOptions [] = {
 	{ "recurse",        &Option.recurse,                false, STAGE_ANY },
 #endif
 	{ "verbose",        &ctags_verbose,                false, STAGE_ANY },
+#ifdef WIN32
+	{ "use-slash-as-filename-separator", (bool *)&Option.useSlashAsFilenameSeparator, false, STAGE_ANY },
+#endif
 	{ "with-list-header", &localOption.withListHeader,       true,  STAGE_ANY },
 	{ "_fatal-warnings",&Option.fatalWarnings,          false, STAGE_ANY },
 };

main/options_p.h

@@ -120,6 +120,12 @@ typedef struct sOptionValues {
 	enum interactiveMode { INTERACTIVE_NONE = 0,
 						   INTERACTIVE_DEFAULT,
 						   INTERACTIVE_SANDBOX, } interactive; /* --interactive */
+#ifdef WIN32
+	enum filenameSepOp { FILENAME_SEP_UNSET      = -1,
+						 FILENAME_SEP_NO_REPLACE = false,
+						 FILENAME_SEP_USE_SLASH  = true,
+	} useSlashAsFilenameSeparator; /* --use-slash-as-filename-separator */
+#endif
 #ifdef DEBUG
 	unsigned long breakLine;/* -b  input line at which to call lineBreak() */
 #endif

main/writer-ctags.c

@@ -38,10 +38,20 @@ struct rejection {
 	bool rejectionInThisInput;
 };
 
+static void *beginUCtagsFile (tagWriter *writer CTAGS_ATTR_UNUSED, MIO * mio CTAGS_ATTR_UNUSED,
+							  void *clientData CTAGS_ATTR_UNUSED)
+{
+#ifdef WIN32
+	if (Option.useSlashAsFilenameSeparator == FILENAME_SEP_UNSET)
+		Option.useSlashAsFilenameSeparator = FILENAME_SEP_USE_SLASH;
+#endif
+	return NULL;
+}
+
 tagWriter uCtagsWriter = {
 	.writeEntry = writeCtagsEntry,
 	.writePtagEntry = writeCtagsPtagEntry,
-	.preWriteEntry = NULL,
+	.preWriteEntry = beginUCtagsFile,
 	.postWriteEntry = NULL,
 	.rescanFailedEntry = NULL,
 	.treatFieldAsFixed = treatFieldAsFixed,