Move syntax name/extension utilities to public API

4 files changed, 108 insertions, 50 deletions

diff --git a/serd/serd.h b/serd/serd.h
index ff417b6c..ba143d8d 100644
--- a/serd/serd.h
+++ b/serd/serd.h
@@ -402,6 +402,41 @@ typedef size_t (*SerdWriteFunc)(const void* buf,
 
 /**
    @}
+   @name Syntax Utilities
+   @{
+*/
+
+/**
+   Get a syntax by name.
+
+   Case-insensitive, supports "Turtle", "NTriples", "NQuads", and "TriG".  Zero
+   is returned if the name is not recognized.
+*/
+SERD_API
+SerdSyntax
+serd_syntax_by_name(const char* name);
+
+/**
+   Guess a syntax from a filename.
+
+   This uses the file extension to guess the syntax of a file.  Zero is
+   returned if the extension is not recognized.
+*/
+SERD_API
+SerdSyntax
+serd_guess_syntax(const char* filename);
+
+/**
+   Return whether a syntax can represent multiple graphs.
+
+   @return True for SERD_NQUADS and SERD_TRIG, false otherwise.
+*/
+SERD_API
+bool
+serd_syntax_has_graphs(SerdSyntax syntax);
+
+/**
+   @}
    @name URI
    @{
 */
diff --git a/src/serdi.c b/src/serdi.c
index fcb4274e..71c4e683 100644
--- a/src/serdi.c
+++ b/src/serdi.c
@@ -14,8 +14,6 @@
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
 
-#include "serd_config.h"
-#include "string_utils.h"
 #include "system.h"
 
 #include "serd/serd.h"
@@ -29,51 +27,10 @@
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
 
 #define SERDI_ERROR(msg)       fprintf(stderr, "serdi: " msg)
 #define SERDI_ERRORF(fmt, ...) fprintf(stderr, "serdi: " fmt, __VA_ARGS__)
 
-typedef struct {
-	SerdSyntax  syntax;
-	const char* name;
-	const char* extension;
-} Syntax;
-
-static const Syntax syntaxes[] = {
-	{SERD_TURTLE,   "turtle",   ".ttl"},
-	{SERD_NTRIPLES, "ntriples", ".nt"},
-	{SERD_NQUADS,   "nquads",   ".nq"},
-	{SERD_TRIG,     "trig",     ".trig"},
-	{(SerdSyntax)0, NULL, NULL}
-};
-
-static SerdSyntax
-get_syntax(const char* name)
-{
-	for (const Syntax* s = syntaxes; s->name; ++s) {
-		if (!serd_strncasecmp(s->name, name, strlen(name))) {
-			return s->syntax;
-		}
-	}
-	SERDI_ERRORF("unknown syntax `%s'\n", name);
-	return (SerdSyntax)0;
-}
-
-static SerdSyntax
-guess_syntax(const char* filename)
-{
-	const char* ext = strrchr(filename, '.');
-	if (ext) {
-		for (const Syntax* s = syntaxes; s->name; ++s) {
-			if (!serd_strncasecmp(s->extension, ext, strlen(ext))) {
-				return s->syntax;
-			}
-		}
-	}
-	return (SerdSyntax)0;
-}
-
 static int
 print_version(void)
 {
@@ -175,7 +132,7 @@ main(int argc, char** argv)
 		} else if (argv[a][1] == 'i') {
 			if (++a == argc) {
 				return missing_arg(argv[0], 'i');
-			} else if (!(input_syntax = get_syntax(argv[a]))) {
+			} else if (!(input_syntax = serd_syntax_by_name(argv[a]))) {
 				return print_usage(argv[0], true);
 			}
 		} else if (argv[a][1] == 'k') {
@@ -192,7 +149,7 @@ main(int argc, char** argv)
 		} else if (argv[a][1] == 'o') {
 			if (++a == argc) {
 				return missing_arg(argv[0], 'o');
-			} else if (!(output_syntax = get_syntax(argv[a]))) {
+			} else if (!(output_syntax = serd_syntax_by_name(argv[a]))) {
 				return print_usage(argv[0], true);
 			}
 		} else if (argv[a][1] == 'p') {
@@ -228,15 +185,13 @@ main(int argc, char** argv)
 
 	const char* input = argv[a++];
 
-	if (!input_syntax && !(input_syntax = guess_syntax(input))) {
+	if (!input_syntax && !(input_syntax = serd_guess_syntax(input))) {
 		input_syntax = SERD_TRIG;
 	}
 
+	const bool input_has_graphs = serd_syntax_has_graphs(input_syntax);
 	if (!output_syntax) {
-		output_syntax = (
-			(input_syntax == SERD_TURTLE || input_syntax == SERD_NTRIPLES)
-			? SERD_NTRIPLES
-			: SERD_NQUADS);
+		output_syntax = input_has_graphs ? SERD_NQUADS : SERD_NTRIPLES;
 	}
 
 	SerdNode* base = NULL;
diff --git a/src/syntax.c b/src/syntax.c
new file mode 100644
index 00000000..8f091a1d
--- /dev/null
+++ b/src/syntax.c
@@ -0,0 +1,67 @@
+/*
+  Copyright 2011-2020 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "string_utils.h"
+
+#include "serd/serd.h"
+
+#include <stdbool.h>
+#include <string.h>
+
+typedef struct {
+	const char* name;
+	const char* extension;
+	SerdSyntax  syntax;
+} Syntax;
+
+static const Syntax syntaxes[] = {
+	{"turtle",   ".ttl",  SERD_TURTLE},
+	{"ntriples", ".nt",   SERD_NTRIPLES},
+	{"nquads",   ".nq",   SERD_NQUADS},
+	{"trig",     ".trig", SERD_TRIG},
+	{NULL,       NULL,	  (SerdSyntax)0},
+};
+
+SerdSyntax
+serd_syntax_by_name(const char* const name)
+{
+	for (const Syntax* s = syntaxes; s->name; ++s) {
+		if (!serd_strncasecmp(s->name, name, strlen(name))) {
+			return s->syntax;
+		}
+	}
+	return (SerdSyntax)0;
+}
+
+SerdSyntax
+serd_guess_syntax(const char* const filename)
+{
+	const char* ext = strrchr(filename, '.');
+	if (ext) {
+		for (const Syntax* s = syntaxes; s->name; ++s) {
+			if (!serd_strncasecmp(s->extension, ext, strlen(ext))) {
+				return s->syntax;
+			}
+		}
+	}
+	return (SerdSyntax)0;
+}
+
+bool
+serd_syntax_has_graphs(const SerdSyntax syntax)
+{
+	return syntax == SERD_NQUADS || syntax == SERD_TRIG;
+}
diff --git a/wscript b/wscript
index f344f1c2..fb52a005 100644
--- a/wscript
+++ b/wscript
@@ -150,6 +150,7 @@ lib_source = ['src/base64.c',
               'src/node.c',
               'src/reader.c',
               'src/string.c',
+              'src/syntax.c',
               'src/system.c',
               'src/uri.c',
               'src/world.c',