[gtk+/wip/otte/shader: 72/150] gsksltokenizer: Parse strings

[Benjamin Otte <otte src gnome org>]

commit c2a60847f46b40f5618bfb76edcd8730aa686db7
Author: Benjamin Otte <otte redhat com>
Date:   Mon Oct 2 00:24:32 2017 +0200

    gsksltokenizer: Parse strings
    
    And when we encounter any strings in the preprocessor, we promptly emit
    an error and skip them. But we do that after the preprocessor runs, so
    we can access strings inside the preprocessor.

 gsk/gskslpreprocessor.c     |    6 ++++++
 gsk/gsksltokenizer.c        |   42 ++++++++++++++++++++++++++++++++++++++++++
 gsk/gsksltokenizerprivate.h |    1 +
 3 files changed, 49 insertions(+), 0 deletions(-)
---
diff --git a/gsk/gskslpreprocessor.c b/gsk/gskslpreprocessor.c
index 11f39df..eb22aaa 100644
--- a/gsk/gskslpreprocessor.c
+++ b/gsk/gskslpreprocessor.c
@@ -224,6 +224,12 @@ gsk_sl_preprocessor_append_token (GskSlPreprocessor *preproc,
       gsk_sl_token_init_from_identifier (&pp->token, ident);
       g_free (ident);
     }
+  else if (gsk_sl_token_is (&pp->token, GSK_SL_TOKEN_STRING))
+    {
+      gsk_sl_preprocessor_error_full (preproc, PREPROCESSOR, &pp->location, "Unexpected string.");
+      gsk_sl_preprocessor_clear_token (pp);
+      return;
+    }
 
   g_array_append_val (preproc->tokens, *pp);
 }
diff --git a/gsk/gsksltokenizer.c b/gsk/gsksltokenizer.c
index 292454f..3aa0b70 100644
--- a/gsk/gsksltokenizer.c
+++ b/gsk/gsksltokenizer.c
@@ -85,6 +85,7 @@ gsk_sl_token_clear (GskSlToken *token)
   switch (token->type)
     {
     case GSK_SL_TOKEN_IDENTIFIER:
+    case GSK_SL_TOKEN_STRING:
       g_free (token->str);
       break;
 
@@ -323,6 +324,7 @@ gsk_sl_token_copy (GskSlToken       *dest,
   switch (src->type)
     {
     case GSK_SL_TOKEN_IDENTIFIER:
+    case GSK_SL_TOKEN_STRING:
       dest->str = g_strdup (src->str);
       break;
 
@@ -910,6 +912,12 @@ gsk_sl_token_print (const GskSlToken *token,
       g_string_append (string, token->str);
       break;
 
+    case GSK_SL_TOKEN_STRING:
+      g_string_append_c (string, '"');
+      g_string_append (string, token->str);
+      g_string_append_c (string, '"');
+      break;
+
     case GSK_SL_TOKEN_FLOATCONSTANT:
       g_ascii_dtostr (buf, G_ASCII_DTOSTR_BUF_SIZE, token->f);
       g_string_append (string, buf);
@@ -1734,6 +1742,36 @@ gsk_sl_token_reader_read_identifier (GskSlTokenReader  *reader,
   token->str = g_string_free (string, FALSE);
 }
 
+static void
+gsk_sl_token_reader_read_string (GskSlTokenReader  *reader,
+                                 GskSlToken        *token,
+                                 GError           **error)
+{
+  GString *string;
+  char c;
+
+  g_assert (gsk_sl_token_reader_get (reader, 0) == '"');
+  gsk_sl_token_reader_consume (reader, 1);
+
+  string = g_string_new ("");
+
+  for (c = gsk_sl_token_reader_get (reader, 0);
+       c != '"' && c != 0;
+       c = gsk_sl_token_reader_get (reader, 0))
+    {
+      g_string_append_c (string, c);
+      gsk_sl_token_reader_consume (reader, 1);
+    }
+
+  if (c == 0)
+    set_parse_error (error, "Unterminated string literal.");
+  else
+    gsk_sl_token_reader_consume (reader, 1);
+
+  gsk_sl_token_init (token, GSK_SL_TOKEN_STRING);
+  token->str = g_string_free (string, FALSE);
+}
+
 gboolean
 gsk_sl_string_is_valid_identifier (const char *ident)
 {
@@ -1840,6 +1878,10 @@ gsk_sl_tokenizer_read_token (GskSlTokenizer *tokenizer,
         }
       break;
 
+    case '"':
+      gsk_sl_token_reader_read_string (&reader, token, &error);
+      break;
+
     case '<':
       switch (gsk_sl_token_reader_get (&reader, 1))
         {
diff --git a/gsk/gsksltokenizerprivate.h b/gsk/gsksltokenizerprivate.h
index e968d31..381a851 100644
--- a/gsk/gsksltokenizerprivate.h
+++ b/gsk/gsksltokenizerprivate.h
@@ -29,6 +29,7 @@ typedef enum {
   GSK_SL_TOKEN_WHITESPACE,
   GSK_SL_TOKEN_COMMENT,
   GSK_SL_TOKEN_SINGLE_LINE_COMMENT,
+  GSK_SL_TOKEN_STRING,
   /* real tokens */
   GSK_SL_TOKEN_CONST,
   GSK_SL_TOKEN_BOOL,