From 9c1f7dd3807badafb665056cd242b63ae41dc7db Mon Sep 17 00:00:00 2001
From: ejurgensen <espenjurgensen@gmail.com>
Date: Fri, 14 Jan 2022 22:27:35 +0100
Subject: [PATCH] [smartpl] Add ESCAPE to LIKE queries where the value contains
 % and _

Plus various minor improvements
---
 src/parsers/smartpl_lexer.l  |  1 +
 src/parsers/smartpl_parser.y | 52 +++++++++++++++++++-----------------
 src/smartpl_query.c          |  5 ++++
 3 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/src/parsers/smartpl_lexer.l b/src/parsers/smartpl_lexer.l
index 3b6951fe..e423b5cf 100644
--- a/src/parsers/smartpl_lexer.l
+++ b/src/parsers/smartpl_lexer.l
@@ -50,6 +50,7 @@
 
 %option case-insensitive
 
+/* quoted \"(\\(.|\n)|[^\\"\n])*\" */
 quoted \"[^\"\n]*[\"\n]
 yyyymmdd  [0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]
 
diff --git a/src/parsers/smartpl_parser.y b/src/parsers/smartpl_parser.y
index dcde356c..e4ebaea5 100644
--- a/src/parsers/smartpl_parser.y
+++ b/src/parsers/smartpl_parser.y
@@ -188,31 +188,9 @@ int smartpl_lex_parse(struct smartpl_result *result, const char *input);
 %code top {
 #ifndef DEBUG_PARSER_MOCK
 #include "db.h"
+#include "misc.h"
 #else
-enum data_kind {
-  DATA_KIND_FILE = 0,
-  DATA_KIND_HTTP = 1,
-  DATA_KIND_SPOTIFY = 2,
-  DATA_KIND_PIPE = 3,
-};
-
-enum media_kind {
-  MEDIA_KIND_MUSIC = 1,
-  MEDIA_KIND_MOVIE = 2,
-  MEDIA_KIND_PODCAST = 4,
-  MEDIA_KIND_AUDIOBOOK = 8,
-  MEDIA_KIND_MUSICVIDEO = 32,
-  MEDIA_KIND_TVSHOW = 64,
-};
-
-static char * db_escape_string(const char *str)
-{
-  char *new = strdup(str);
-  char *ptr;
-  while ((ptr = strpbrk(new, "\\'")))
-   *ptr = 'X';
-  return new;
-}
+#include "owntonefunctions.h"
 #endif
 }
 
@@ -253,6 +231,27 @@ enum sql_append_type {
 
 static void sql_from_ast(struct smartpl_result *, struct result_part *, struct ast *);
 
+// Escapes any '%' or '_' that might be in the string
+static void sql_like_escape(char **value, char *escape_char)
+{
+  char *s = *value;
+  size_t len = strlen(s);
+  char *new;
+
+  *escape_char = 0;
+
+  // Fast path, nothing to escape
+  if (!strpbrk(s, "_%"))
+    return;
+
+  len = 2 * len; // Enough for every char to be escaped
+  new = realloc(s, len);
+  safe_snreplace(new, len, "%", "\\%");
+  safe_snreplace(new, len, "_", "\\_");
+  *escape_char = '\\';
+  *value = new;
+}
+
 static void sql_str_escape(char **value)
 {
   char *old = *value;
@@ -285,6 +284,8 @@ static void sql_append(struct smartpl_result *result, struct result_part *part,
 
 static void sql_append_recursive(struct smartpl_result *result, struct result_part *part, struct ast *a, const char *op, const char *op_not, bool is_not, enum sql_append_type append_type)
 {
+  char escape_char;
+
   switch (append_type)
   {
     case SQL_APPEND_OPERATOR:
@@ -301,8 +302,11 @@ static void sql_append_recursive(struct smartpl_result *result, struct result_pa
     case SQL_APPEND_OPERATOR_LIKE:
       sql_from_ast(result, part, a->l);
       sql_append(result, part, " %s '%%", is_not ? op_not : op);
+      sql_like_escape((char **)(&a->r->data), &escape_char);
       sql_from_ast(result, part, a->r);
       sql_append(result, part, "%%'");
+      if (escape_char)
+        sql_append(result, part, " ESCAPE '%c'", escape_char);
       break;
     case SQL_APPEND_FIELD:
       assert(a->l == NULL);
diff --git a/src/smartpl_query.c b/src/smartpl_query.c
index 4117f0e1..1f7566c2 100644
--- a/src/smartpl_query.c
+++ b/src/smartpl_query.c
@@ -90,6 +90,8 @@ smartpl_query_parse_string(struct smartpl *smartpl, const char *expression)
 {
   struct smartpl_result result;
 
+  DPRINTF(E_SPAM, L_SCAN, "Parse smartpl query input '%s'\n", expression);
+
   if (smartpl_lex_parse(&result, expression) != 0)
     {
       DPRINTF(E_LOG, L_SCAN, "Could not parse '%s': %s\n", expression, result.errmsg);
@@ -110,6 +112,9 @@ smartpl_query_parse_string(struct smartpl *smartpl, const char *expression)
   smartpl->order = safe_strdup(result.order);
   smartpl->limit = result.limit;
 
+  DPRINTF(E_SPAM, L_SCAN, "Parse smartpl query output '%s': WHERE %s HAVING %s ORDER BY %s LIMIT %d\n",
+    smartpl->title, smartpl->query_where, smartpl->having, smartpl->order, smartpl->limit);
+
   return 0;
 }