Add SerdCursor to public API

10 files changed, 291 insertions, 37 deletions

diff --git a/serd/serd.h b/serd/serd.h
index acf154a4..0a05c395 100644
--- a/serd/serd.h
+++ b/serd/serd.h
@@ -69,6 +69,11 @@ typedef struct SerdWorldImpl SerdWorld;
 typedef struct SerdStatementImpl SerdStatement;
 
 /**
+   Cursor, the origin of a statement in a document.
+*/
+typedef struct SerdCursorImpl SerdCursor;
+
+/**
    Environment.
 
    Represents the state required to resolve a CURIE or relative URI, e.g. the
@@ -255,12 +260,10 @@ typedef struct {
    An error description.
 */
 typedef struct {
-	SerdStatus  status;    /**< Error code */
-	const char* filename;  /**< File where error was encountered, or NULL */
-	unsigned    line;      /**< Line where error was encountered, or 0 */
-	unsigned    col;       /**< Column where error was encountered */
-	const char* fmt;       /**< Message format string (printf style) */
-	va_list*    args;      /**< Arguments for fmt */
+	SerdStatus        status;  /**< Error code */
+	const SerdCursor* cursor;  /**< Origin of error, or NULL */
+	const char*       fmt;     /**< Message format string (printf style) */
+	va_list*          args;    /**< Arguments for fmt */
 } SerdError;
 
 /**
@@ -1112,7 +1115,7 @@ serd_reader_start_stream(SerdReader*         reader,
                          SerdReadFunc        read_func,
                          SerdStreamErrorFunc error_func,
                          void*               stream,
-                         const char*         name,
+                         const SerdNode*     name,
                          size_t              page_size);
 
 /**
@@ -1120,7 +1123,9 @@ serd_reader_start_stream(SerdReader*         reader,
 */
 SERD_API
 SerdStatus
-serd_reader_start_string(SerdReader* reader, const char* utf8);
+serd_reader_start_string(SerdReader*     reader,
+                         const char*     utf8,
+                         const SerdNode* name);
 
 /**
    Read a single "chunk" of data during an incremental read.
@@ -1303,6 +1308,70 @@ serd_statement_get_graph(const SerdStatement* statement);
 
 /**
    @}
+   @name Cursor
+   @{
+*/
+
+/**
+   Create a new cursor
+
+   Note that, to minimise model overhead, the cursor does not own the name
+   node, so `name` must have a longer lifetime than the cursor for it to be
+   valid.  That is, serd_cursor_get_name() will return exactly the pointer
+   `name`, not a copy.  For cursors from models, this is the lifetime of the
+   model.  For user-created cursors, the simplest way to handle this is to use
+   `SerdNodes`.
+
+   @param name The name of the document or stream (usually a file URI)
+   @param line The line number in the document (1-based)
+   @param col The column number in the document (1-based)
+   @return A new cursor that must be freed with serd_cursor_free()
+*/
+SERD_API
+SerdCursor*
+serd_cursor_new(const SerdNode* name, unsigned line, unsigned col);
+
+/// Return a copy of `cursor`
+SERD_API
+SerdCursor*
+serd_cursor_copy(const SerdCursor* cursor);
+
+/// Free `cursor`
+SERD_API
+void
+serd_cursor_free(SerdCursor* cursor);
+
+/// Return true iff `lhs` is equal to `rhs`
+SERD_API
+bool
+serd_cursor_equals(const SerdCursor* lhs, const SerdCursor* rhs);
+
+/**
+   Return the document name.
+
+   This is typically a file URI, but may be a descriptive string node for
+   statements that originate from streams.
+*/
+SERD_API
+const SerdNode*
+serd_cursor_get_name(const SerdCursor* cursor);
+
+/**
+   Return the one-relative line number in the document.
+*/
+SERD_API
+unsigned
+serd_cursor_get_line(const SerdCursor* cursor);
+
+/**
+   Return the zero-relative column number in the line.
+*/
+SERD_API
+unsigned
+serd_cursor_get_column(const SerdCursor* cursor);
+
+/**
+   @}
    @}
 */
 
diff --git a/src/byte_source.c b/src/byte_source.c
index b9e9ff4b..34c75736 100644
--- a/src/byte_source.c
+++ b/src/byte_source.c
@@ -48,11 +48,9 @@ serd_byte_source_open_source(SerdByteSource*     source,
                              SerdStreamErrorFunc error_func,
                              SerdStreamCloseFunc close_func,
                              void*               stream,
-                             const char*         name,
+                             const SerdNode*     name,
                              size_t              page_size)
 {
-	const Cursor cur = { name, 1, 1 };
-
 	memset(source, '\0', sizeof(*source));
 	source->read_func   = read_func;
 	source->error_func  = error_func;
@@ -60,9 +58,12 @@ serd_byte_source_open_source(SerdByteSource*     source,
 	source->stream      = stream;
 	source->page_size   = page_size;
 	source->buf_size    = page_size;
-	source->cur         = cur;
+	source->name        = serd_node_copy(name);
 	source->from_stream = true;
 
+	const SerdCursor cur = { source->name, 1, 1 };
+	source->cur = cur;
+
 	if (page_size > 1) {
 		source->file_buf = (uint8_t*)serd_allocate_buffer(page_size);
 		source->read_buf = source->file_buf;
@@ -89,13 +90,18 @@ serd_byte_source_prepare(SerdByteSource* source)
 }
 
 SerdStatus
-serd_byte_source_open_string(SerdByteSource* source, const char* utf8)
+serd_byte_source_open_string(SerdByteSource* source,
+                             const char*     utf8,
+                             const SerdNode* name)
 {
-	const Cursor cur = { "(string)", 1, 1 };
-
 	memset(source, '\0', sizeof(*source));
-	source->cur      = cur;
+
+	source->name     = name ? serd_node_copy(name) : serd_new_string("string");
 	source->read_buf = (const uint8_t*)utf8;
+
+	const SerdCursor cur = {source->name, 1, 1};
+	source->cur          = cur;
+
 	return SERD_SUCCESS;
 }
 
@@ -110,6 +116,7 @@ serd_byte_source_close(SerdByteSource* source)
 	if (source->page_size > 1) {
 		free(source->file_buf);
 	}
+	serd_node_free(source->name);
 	memset(source, '\0', sizeof(*source));
 	return st;
 }
diff --git a/src/byte_source.h b/src/byte_source.h
index 1cb0cfd1..beb9d695 100644
--- a/src/byte_source.h
+++ b/src/byte_source.h
@@ -17,6 +17,8 @@
 #ifndef SERD_BYTE_SOURCE_H
 #define SERD_BYTE_SOURCE_H
 
+#include "cursor.h"
+
 #include "serd/serd.h"
 
 #include <assert.h>
@@ -27,19 +29,14 @@
 typedef int (*SerdStreamCloseFunc)(void*);
 
 typedef struct {
-	const char* filename;
-	unsigned    line;
-	unsigned    col;
-} Cursor;
-
-typedef struct {
 	SerdReadFunc        read_func;    ///< Read function (e.g. fread)
 	SerdStreamErrorFunc error_func;   ///< Error function (e.g. ferror)
 	SerdStreamCloseFunc close_func;   ///< Function for closing stream
 	void*               stream;       ///< Stream (e.g. FILE)
 	size_t              page_size;    ///< Number of bytes to read at a time
 	size_t              buf_size;     ///< Number of bytes in file_buf
-	Cursor              cur;          ///< Cursor for error reporting
+	SerdNode*           name;         ///< Name of stream (referenced by cur)
+	SerdCursor          cur;          ///< Cursor for error reporting
 	uint8_t*            file_buf;     ///< Buffer iff reading pages from a file
 	const uint8_t*      read_buf;     ///< Pointer to file_buf or read_byte
 	size_t              read_head;    ///< Offset into read_buf
@@ -50,7 +47,9 @@ typedef struct {
 } SerdByteSource;
 
 SerdStatus
-serd_byte_source_open_string(SerdByteSource* source, const char* utf8);
+serd_byte_source_open_string(SerdByteSource* source,
+                             const char*     utf8,
+                             const SerdNode* name);
 
 SerdStatus
 serd_byte_source_open_source(SerdByteSource*     source,
@@ -58,7 +57,7 @@ serd_byte_source_open_source(SerdByteSource*     source,
                              SerdStreamErrorFunc error_func,
                              SerdStreamCloseFunc close_func,
                              void*               stream,
-                             const char*         name,
+                             const SerdNode*     name,
                              size_t              page_size);
 
 SerdStatus
diff --git a/src/cursor.c b/src/cursor.c
new file mode 100644
index 00000000..ac9b24a9
--- /dev/null
+++ b/src/cursor.c
@@ -0,0 +1,74 @@
+/*
+  Copyright 2018 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 "cursor.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+SerdCursor*
+serd_cursor_new(const SerdNode* name, unsigned line, unsigned col)
+{
+	SerdCursor* cursor = (SerdCursor*)malloc(sizeof(SerdCursor));
+
+	cursor->file = name;
+	cursor->line = line;
+	cursor->col  = col;
+	return cursor;
+}
+
+SerdCursor*
+serd_cursor_copy(const SerdCursor* cursor)
+{
+	if (!cursor) {
+		return NULL;
+	}
+
+	SerdCursor* copy = (SerdCursor*)malloc(sizeof(SerdCursor));
+	memcpy(copy, cursor, sizeof(SerdCursor));
+	return copy;
+}
+
+void
+serd_cursor_free(SerdCursor* cursor)
+{
+	free(cursor);
+}
+
+bool
+serd_cursor_equals(const SerdCursor* l, const SerdCursor* r)
+{
+	return (l == r || (l && r && serd_node_equals(l->file, r->file) &&
+	                   l->line == r->line && l->col == r->col));
+}
+
+const SerdNode*
+serd_cursor_get_name(const SerdCursor* cursor)
+{
+	return cursor->file;
+}
+
+unsigned
+serd_cursor_get_line(const SerdCursor* cursor)
+{
+	return cursor->line;
+}
+
+unsigned
+serd_cursor_get_column(const SerdCursor* cursor)
+{
+	return cursor->col;
+}
diff --git a/src/cursor.h b/src/cursor.h
new file mode 100644
index 00000000..51fbf6e8
--- /dev/null
+++ b/src/cursor.h
@@ -0,0 +1,28 @@
+/*
+  Copyright 2018 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.
+*/
+
+#ifndef SERD_CURSOR_H
+#define SERD_CURSOR_H
+
+#include "serd/serd.h"
+
+struct SerdCursorImpl {
+	const SerdNode* file;
+	unsigned        line;
+	unsigned        col;
+};
+
+#endif  // SERD_CURSOR_H
diff --git a/src/reader.c b/src/reader.c
index 13fc681d..8bc8edd7 100644
--- a/src/reader.c
+++ b/src/reader.c
@@ -39,8 +39,7 @@ r_err(SerdReader* reader, SerdStatus st, const char* fmt, ...)
 {
 	va_list args;
 	va_start(args, fmt);
-	const Cursor* const cur = &reader->source.cur;
-	const SerdError e = { st, cur->filename, cur->line, cur->col, fmt, &args };
+	const SerdError e = { st, &reader->source.cur, fmt, &args };
 	serd_world_error(reader->world, &e);
 	va_end(args);
 	return st;
@@ -246,7 +245,7 @@ serd_reader_start_stream(SerdReader*         reader,
                          SerdReadFunc        read_func,
                          SerdStreamErrorFunc error_func,
                          void*               stream,
-                         const char*         name,
+                         const SerdNode*     name,
                          size_t              page_size)
 {
 	return serd_byte_source_open_source(
@@ -267,20 +266,25 @@ serd_reader_start_file(SerdReader* reader, const char* uri, bool bulk)
 		return SERD_ERR_UNKNOWN;
 	}
 
-	return serd_byte_source_open_source(
+	SerdNode* const name = serd_new_uri(uri);
+	const SerdStatus st = serd_byte_source_open_source(
 		&reader->source,
 		bulk ? (SerdReadFunc)fread : serd_file_read_byte,
 		(SerdStreamErrorFunc)ferror,
 		(SerdStreamCloseFunc)fclose,
 		fd,
-		uri,
+		name,
 		bulk ? SERD_PAGE_SIZE : 1);
+	serd_node_free(name);
+	return st;
 }
 
 SerdStatus
-serd_reader_start_string(SerdReader* reader, const char* utf8)
+serd_reader_start_string(SerdReader*     reader,
+                         const char*     utf8,
+                         const SerdNode* name)
 {
-	return serd_byte_source_open_string(&reader->source, utf8);
+	return serd_byte_source_open_string(&reader->source, utf8, name);
 }
 
 static SerdStatus
diff --git a/src/serdi.c b/src/serdi.c
index 76e1c476..5140dd58 100644
--- a/src/serdi.c
+++ b/src/serdi.c
@@ -247,15 +247,18 @@ main(int argc, char** argv)
 	serd_reader_add_blank_prefix(reader, add_prefix);
 	serd_node_free(root);
 
-	SerdStatus status = SERD_SUCCESS;
+	SerdStatus status     = SERD_SUCCESS;
+	SerdNode*  input_name = NULL;
 	if (from_string) {
-		status = serd_reader_start_string(reader, input);
+		input_name = serd_new_string("string");
+		status = serd_reader_start_string(reader, input, input_name);
 	} else if (from_stdin) {
+		input_name = serd_new_string("stdin");
 		status = serd_reader_start_stream(reader,
 		                                  serd_file_read_byte,
 		                                  (SerdStreamErrorFunc)ferror,
 		                                  stdin,
-		                                  "(stdin)",
+		                                  input_name,
 		                                  1);
 	} else {
 		status = serd_reader_start_file(reader, input, bulk_read);
diff --git a/src/world.c b/src/world.c
index 27feeac6..d43a2909 100644
--- a/src/world.c
+++ b/src/world.c
@@ -18,6 +18,7 @@
 
 #include "world.h"
 
+#include "cursor.h"
 #include "node.h"
 #include "serd_config.h"
 
@@ -54,7 +55,14 @@ serd_world_error(const SerdWorld* world, const SerdError* e)
 	if (world->error_sink) {
 		world->error_sink(world->error_handle, e);
 	} else {
-		fprintf(stderr, "error: %s:%u:%u: ", e->filename, e->line, e->col);
+		fprintf(stderr, "error: ");
+		if (e->cursor) {
+			fprintf(stderr,
+			        "%s:%u:%u: ",
+			        serd_node_get_string(e->cursor->file),
+			        e->cursor->line,
+			        e->cursor->col);
+		}
 		vfprintf(stderr, e->fmt, *e->args);
 	}
 	return e->status;
@@ -65,7 +73,7 @@ serd_world_errorf(const SerdWorld* world, SerdStatus st, const char* fmt, ...)
 {
 	va_list args;
 	va_start(args, fmt);
-	const SerdError e = { st, NULL, 0, 0, fmt, &args };
+	const SerdError e = { st, NULL, fmt, &args };
 	serd_world_error(world, &e);
 	va_end(args);
 	return st;
diff --git a/tests/cursor_test.c b/tests/cursor_test.c
new file mode 100644
index 00000000..cd2044f9
--- /dev/null
+++ b/tests/cursor_test.c
@@ -0,0 +1,59 @@
+/*
+  Copyright 2019 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.
+*/
+
+#undef NDEBUG
+
+#include "serd/serd.h"
+
+#include <assert.h>
+#include <stddef.h>
+
+int
+main(void)
+{
+	SerdNode* const   node   = serd_new_string("node");
+	SerdCursor* const cursor = serd_cursor_new(node, 46, 2);
+
+	assert(serd_cursor_get_name(cursor) == node);
+	assert(serd_cursor_get_line(cursor) == 46);
+	assert(serd_cursor_get_column(cursor) == 2);
+
+	SerdCursor* const copy = serd_cursor_copy(cursor);
+
+	assert(serd_cursor_equals(cursor, copy));
+	assert(!serd_cursor_copy(NULL));
+
+	SerdNode* const   other_node = serd_new_string("other");
+	SerdCursor* const other_file = serd_cursor_new(other_node, 46, 2);
+	SerdCursor* const other_line = serd_cursor_new(node, 47, 2);
+	SerdCursor* const other_col  = serd_cursor_new(node, 46, 3);
+
+	assert(!serd_cursor_equals(cursor, other_file));
+	assert(!serd_cursor_equals(cursor, other_line));
+	assert(!serd_cursor_equals(cursor, other_col));
+	assert(!serd_cursor_equals(cursor, NULL));
+	assert(!serd_cursor_equals(NULL, cursor));
+
+	serd_cursor_free(other_col);
+	serd_cursor_free(other_line);
+	serd_cursor_free(other_file);
+	serd_node_free(other_node);
+	serd_cursor_free(copy);
+	serd_cursor_free(cursor);
+	serd_node_free(node);
+
+	return 0;
+}
diff --git a/wscript b/wscript
index 06e47ee8..e2a4cbc3 100644
--- a/wscript
+++ b/wscript
@@ -82,6 +82,7 @@ lib_headers = ['src/reader.h']
 
 lib_source = ['src/base64.c',
               'src/byte_source.c',
+              'src/cursor.c',
               'src/env.c',
               'src/n3.c',
               'src/node.c',
@@ -151,6 +152,7 @@ def build(bld):
 
         # Test programs
         for prog in [('serdi_static', 'src/serdi.c'),
+                     ('cursor_test', 'tests/cursor_test.c'),
                      ('serd_test', 'tests/serd_test.c')]:
             bld(features     = 'c cprogram',
                 source       = prog[1],
@@ -414,6 +416,7 @@ def test(tst):
     srcdir = tst.path.abspath()
 
     with tst.group('Unit') as check:
+        check(['./cursor_test'])
         check(['./serd_test'])
 
     def test_syntax_io(check, in_name, check_name, lang):