[smartpl/filescanner] Refactor smart playlist parsing

Moves the actual parsing with ANTLR3 out of filescanner.c to allow
future reuse in different context (JSON api)

src/Makefile.am

@@ -124,6 +124,7 @@ forked_daapd_SOURCES = main.c \
 	rng.c rng.h \
 	rsp_query.c rsp_query.h \
 	daap_query.c daap_query.h \
+	smartpl_query.c smartpl_query.h \
 	player.c player.h \
 	worker.c worker.h \
 	input.h input.c \

src/library/filescanner_smartpl.c

@@ -34,144 +34,13 @@
 #include "logger.h"
 #include "db.h"
 #include "misc.h"
+#include "smartpl_query.h"
 
-#include "SMARTPLLexer.h"
-#include "SMARTPLParser.h"
-#include "SMARTPL2SQL.h"
-
-static int
-smartpl_parse_file(const char *file, struct playlist_info *pli)
-{
-  pANTLR3_INPUT_STREAM input;
-  pSMARTPLLexer lxr;
-  pANTLR3_COMMON_TOKEN_STREAM tstream;
-  pSMARTPLParser psr;
-  SMARTPLParser_playlist_return qtree;
-  pANTLR3_COMMON_TREE_NODE_STREAM nodes;
-  pSMARTPL2SQL sqlconv;
-  SMARTPL2SQL_playlist_return plreturn;
-  int ret;
-
-#if ANTLR3C_NEW_INPUT
-  input = antlr3FileStreamNew((pANTLR3_UINT8) file, ANTLR3_ENC_8BIT);
-#else
-  input = antlr3AsciiFileStreamNew((pANTLR3_UINT8) file);
-#endif
-
-
-  // The input will be created successfully, providing that there is enough memory and the file exists etc
-  if (input == NULL)
-    {
-      DPRINTF(E_LOG, L_SCAN, "Unable to open smart playlist file %s\n", file);
-      return -1;
-    }
-
-  lxr = SMARTPLLexerNew(input);
-
-  // Need to check for errors
-  if (lxr == NULL)
-    {
-      DPRINTF(E_LOG, L_SCAN, "Could not create SMARTPL lexer\n");
-      ret = -1;
-      goto lxr_fail;
-    }
-
-  tstream = antlr3CommonTokenStreamSourceNew(ANTLR3_SIZE_HINT, TOKENSOURCE(lxr));
-
-  if (tstream == NULL)
-    {
-      DPRINTF(E_LOG, L_SCAN, "Could not create SMARTPL token stream\n");
-      ret = -1;
-      goto tkstream_fail;
-    }
-
-  // Finally, now that we have our lexer constructed, we can create the parser
-  psr = SMARTPLParserNew(tstream);  // CParserNew is generated by ANTLR3
-
-  if (tstream == NULL)
-    {
-      DPRINTF(E_LOG, L_SCAN, "Could not create SMARTPL parser\n");
-      ret = -1;
-      goto psr_fail;
-    }
-
-  qtree = psr->playlist(psr);
-
-  /* Check for parser errors */
-  if (psr->pParser->rec->state->errorCount > 0)
-    {
-      DPRINTF(E_LOG, L_SCAN, "SMARTPL query parser terminated with %d errors\n", psr->pParser->rec->state->errorCount);
-      ret = -1;
-      goto psr_error;
-    }
-
-  DPRINTF(E_DBG, L_SCAN, "SMARTPL query AST:\n\t%s\n", qtree.tree->toStringTree(qtree.tree)->chars);
-
-  nodes = antlr3CommonTreeNodeStreamNewTree(qtree.tree, ANTLR3_SIZE_HINT);
-  if (!nodes)
-    {
-      DPRINTF(E_LOG, L_SCAN, "Could not create node stream\n");
-      ret = -1;
-      goto psr_error;
-    }
-
-  sqlconv = SMARTPL2SQLNew(nodes);
-  if (!sqlconv)
-    {
-      DPRINTF(E_LOG, L_SCAN, "Could not create SQL converter\n");
-      ret = -1;
-      goto sql_fail;
-    }
-
-  plreturn = sqlconv->playlist(sqlconv);
-
-  /* Check for tree parser errors */
-  if (sqlconv->pTreeParser->rec->state->errorCount > 0)
-    {
-      DPRINTF(E_LOG, L_SCAN, "SMARTPL query tree parser terminated with %d errors\n", sqlconv->pTreeParser->rec->state->errorCount);
-      ret = -1;
-      goto sql_error;
-    }
-
-  if (plreturn.title && plreturn.query)
-    {
-      DPRINTF(E_DBG, L_SCAN, "SMARTPL SQL title '%s' query: -%s-\n", plreturn.title->chars, plreturn.query->chars);
-
-      if (pli->title)
-	free(pli->title);
-      pli->title = strdup((char *)plreturn.title->chars);
-
-      if (pli->query)
-	free(pli->query);
-      pli->query = strdup((char *)plreturn.query->chars);
-
-      ret = 0;
-    }
-  else
-    {
-      DPRINTF(E_LOG, L_SCAN, "Invalid SMARTPL query\n");
-      ret = -1;
-    }
-
- sql_error:
-  sqlconv->free(sqlconv);
- sql_fail:
-  nodes->free(nodes);
- psr_error:
-  psr->free(psr);
- psr_fail:
-  tstream->free(tstream);
- tkstream_fail:
-  lxr->free(lxr);
- lxr_fail:
-  input->close(input);
-
-  return ret;
-}
 
 void
 scan_smartpl(const char *file, time_t mtime, int dir_id)
 {
+  struct smartpl smartpl;
   struct playlist_info *pli;
   int pl_id;
   char virtual_path[PATH_MAX];
@@ -200,15 +69,27 @@ scan_smartpl(const char *file, time_t mtime, int dir_id)
 
   pli->directory_id = dir_id;
 
-  ret = smartpl_parse_file(file, pli);
+  memset(&smartpl, 0, sizeof(struct smartpl));
+  ret = smartpl_query_parse_file(&smartpl, file);
   if (ret < 0)
     {
       DPRINTF(E_LOG, L_SCAN, "Error parsing smart playlist '%s'\n", file);
 
       free_pli(pli, 0);
+      free_smartpl(&smartpl, 1);
       return;
     }
 
+  if (pli->title)
+    free(pli->title);
+  pli->title = strdup(smartpl.title);
+
+  if (pli->query)
+    free(pli->query);
+  pli->query = strdup(smartpl.query_where);
+
+  free_smartpl(&smartpl, 1);
+
   if (pli->id)
     {
       pl_id = pli->id;

src/smartpl_query.c

@@ -0,0 +1,234 @@
+/*
+ * Copyright (C) 2018 Christian Meffert <christian.meffert@googlemail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <limits.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+
+#include "smartpl_query.h"
+#include "logger.h"
+#include "misc.h"
+
+#include "SMARTPLLexer.h"
+#include "SMARTPLParser.h"
+#include "SMARTPL2SQL.h"
+
+
+static int
+parse_input(struct smartpl *smartpl, pANTLR3_INPUT_STREAM input)
+{
+  pSMARTPLLexer lxr;
+  pANTLR3_COMMON_TOKEN_STREAM tstream;
+  pSMARTPLParser psr;
+  SMARTPLParser_playlist_return qtree;
+  pANTLR3_COMMON_TREE_NODE_STREAM nodes;
+  pSMARTPL2SQL sqlconv;
+  SMARTPL2SQL_playlist_return plreturn;
+  int ret;
+
+  lxr = SMARTPLLexerNew(input);
+
+  // Need to check for errors
+  if (lxr == NULL)
+    {
+      DPRINTF(E_LOG, L_SCAN, "Could not create SMARTPL lexer\n");
+      ret = -1;
+      goto lxr_fail;
+    }
+
+  tstream = antlr3CommonTokenStreamSourceNew(ANTLR3_SIZE_HINT, TOKENSOURCE(lxr));
+
+  if (tstream == NULL)
+    {
+      DPRINTF(E_LOG, L_SCAN, "Could not create SMARTPL token stream\n");
+      ret = -1;
+      goto tkstream_fail;
+    }
+
+  // Finally, now that we have our lexer constructed, we can create the parser
+  psr = SMARTPLParserNew(tstream);  // CParserNew is generated by ANTLR3
+
+  if (tstream == NULL)
+    {
+      DPRINTF(E_LOG, L_SCAN, "Could not create SMARTPL parser\n");
+      ret = -1;
+      goto psr_fail;
+    }
+
+  qtree = psr->playlist(psr);
+
+  /* Check for parser errors */
+  if (psr->pParser->rec->state->errorCount > 0)
+    {
+      DPRINTF(E_LOG, L_SCAN, "SMARTPL query parser terminated with %d errors\n", psr->pParser->rec->state->errorCount);
+      ret = -1;
+      goto psr_error;
+    }
+
+  DPRINTF(E_DBG, L_SCAN, "SMARTPL query AST:\n\t%s\n", qtree.tree->toStringTree(qtree.tree)->chars);
+
+  nodes = antlr3CommonTreeNodeStreamNewTree(qtree.tree, ANTLR3_SIZE_HINT);
+  if (!nodes)
+    {
+      DPRINTF(E_LOG, L_SCAN, "Could not create node stream\n");
+      ret = -1;
+      goto psr_error;
+    }
+
+  sqlconv = SMARTPL2SQLNew(nodes);
+  if (!sqlconv)
+    {
+      DPRINTF(E_LOG, L_SCAN, "Could not create SQL converter\n");
+      ret = -1;
+      goto sql_fail;
+    }
+
+  plreturn = sqlconv->playlist(sqlconv);
+
+  /* Check for tree parser errors */
+  if (sqlconv->pTreeParser->rec->state->errorCount > 0)
+    {
+      DPRINTF(E_LOG, L_SCAN, "SMARTPL query tree parser terminated with %d errors\n", sqlconv->pTreeParser->rec->state->errorCount);
+      ret = -1;
+      goto sql_error;
+    }
+
+  if (plreturn.title && plreturn.query)
+    {
+      DPRINTF(E_DBG, L_SCAN, "SMARTPL SQL title '%s', query: '%s', having: '%s', order by: '%s', limit: %d \n", plreturn.title->chars, plreturn.query->chars, plreturn.having->chars, plreturn.orderby->chars, plreturn.limit);
+
+      if (smartpl->title)
+	free(smartpl->title);
+      smartpl->title = strdup((char *)plreturn.title->chars);
+
+      if (smartpl->query_where)
+	free(smartpl->query_where);
+      smartpl->query_where = strdup((char *)plreturn.query->chars);
+
+      if (smartpl->having)
+	free(smartpl->having);
+      smartpl->having = safe_strdup((char *)plreturn.having->chars);
+
+      if (smartpl->order_by)
+	free(smartpl->order_by);
+      smartpl->order_by = safe_strdup((char *)plreturn.orderby->chars);
+
+      smartpl->limit = plreturn.limit;
+
+      ret = 0;
+    }
+  else
+    {
+      DPRINTF(E_LOG, L_SCAN, "Invalid SMARTPL query\n");
+      ret = -1;
+    }
+
+ sql_error:
+  sqlconv->free(sqlconv);
+ sql_fail:
+  nodes->free(nodes);
+ psr_error:
+  psr->free(psr);
+ psr_fail:
+  tstream->free(tstream);
+ tkstream_fail:
+  lxr->free(lxr);
+ lxr_fail:
+
+  return ret;
+}
+
+int
+smartpl_query_parse_file(struct smartpl *smartpl, const char *file)
+{
+  pANTLR3_INPUT_STREAM input;
+  int ret;
+
+#if ANTLR3C_NEW_INPUT
+  input = antlr3FileStreamNew((pANTLR3_UINT8) file, ANTLR3_ENC_8BIT);
+#else
+  input = antlr3AsciiFileStreamNew((pANTLR3_UINT8) file);
+#endif
+
+  // The input will be created successfully, providing that there is enough memory and the file exists etc
+  if (input == NULL)
+    {
+      DPRINTF(E_LOG, L_SCAN, "Unable to open smart playlist file %s\n", file);
+      return -1;
+    }
+
+  ret = parse_input(smartpl, input);
+  input->close(input);
+
+  return ret;
+}
+
+int
+smartpl_query_parse_string(struct smartpl *smartpl, const char *expression)
+{
+  pANTLR3_INPUT_STREAM input;
+  int ret;
+
+#if ANTLR3C_NEW_INPUT
+  input = antlr3StringStreamNew ((pANTLR3_UINT8)expression, ANTLR3_ENC_8BIT, (ANTLR3_UINT64)strlen(expression), (pANTLR3_UINT8)"SMARTPL expression");
+#else
+  input = antlr3NewAsciiStringInPlaceStream ((pANTLR3_UINT8)expression, (ANTLR3_UINT64)strlen(expression), (pANTLR3_UINT8)"SMARTPL expression");
+#endif
+
+  // The input will be created successfully, providing that there is enough memory and the file exists etc
+  if (input == NULL)
+    {
+      DPRINTF(E_LOG, L_SCAN, "Unable to pars smart pl expression %s\n", expression);
+      return -1;
+    }
+
+  ret = parse_input(smartpl, input);
+  input->close(input);
+
+  return ret;
+}
+
+
+void
+free_smartpl(struct smartpl *smartpl, int content_only)
+{
+  if (!smartpl)
+    return;
+
+  free(smartpl->title);
+  free(smartpl->query_where);
+  free(smartpl->having);
+  free(smartpl->order_by);
+
+  if (!content_only)
+    free(smartpl);
+  else
+    memset(smartpl, 0, sizeof(struct smartpl));
+}
+

src/smartpl_query.h

@@ -0,0 +1,23 @@
+
+#ifndef __SMARTPL_QUERY_H__
+#define __SMARTPL_QUERY_H__
+
+
+struct smartpl {
+  char *title;
+  char *query_where;
+  char *having;
+  char *order_by;
+  int limit;
+};
+
+int
+smartpl_query_parse_file(struct smartpl *smartpl, const char *file);
+
+int
+smartpl_query_parse_string(struct smartpl *smartpl, const char *expression);
+
+void
+free_smartpl(struct smartpl *smartpl, int content_only);
+
+#endif /* __SMARTPL_QUERY_H__ */