implement POSIX regexp support

[project/jsonpath.git] / lexer.c

diff --git a/lexer.c b/lexer.c
index ca5880e..c016d41 100644 (file)
--- a/lexer.c
+++ b/lexer.c
@@ -18,6 +18,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
+#include <regex.h>
 
 #include "ast.h"
 #include "lexer.h"
@@ -236,7 +237,21 @@ parse_string(const char *buf, struct jp_opcode *op, struct jp_state *s)
                                case 'r': *out = '\r'; break;
                                case 't': *out = '\t'; break;
                                case 'v': *out = '\v'; break;
-                               default:  *out = *in; break;
+                               default:
+                                       /* in regexp mode, retain backslash */
+                                       if (q == '/')
+                                       {
+                                               if (rem-- < 1)
+                                               {
+                                                       s->error_pos = s->off + (in - buf);
+                                                       return -3;
+                                               }
+
+                                               *out++ = '\\';
+                                       }
+
+                                       *out = *in;
+                                       break;
                                }
 
                                in++;
@@ -278,6 +293,58 @@ parse_string(const char *buf, struct jp_opcode *op, struct jp_state *s)
 
 
 /*
+ * Parses a regexp literal from the given buffer.
+ *
+ * Returns a negative value on error, otherwise the amount of consumed
+ * characters from the given buffer.
+ *
+ * Error values:
+ *  -1 Unterminated regexp
+ *  -2 Invalid escape sequence
+ *  -3 Regexp literal too long
+ */
+
+static int
+parse_regexp(const char *buf, struct jp_opcode *op, struct jp_state *s)
+{
+       int len = parse_string(buf, op, s);
+       const char *p;
+
+       if (len >= 2)
+       {
+               op->num = REG_NOSUB | REG_NEWLINE;
+
+               for (p = buf + len; p; p++)
+               {
+                       switch (*p)
+                       {
+                       case 'e':
+                               op->num |= REG_EXTENDED;
+                               len++;
+                               break;
+
+                       case 'i':
+                               op->num |= REG_ICASE;
+                               len++;
+                               break;
+
+                       case 's':
+                               op->num &= ~REG_NEWLINE;
+                               len++;
+                               break;
+
+                       default:
+                               return len;
+                       }
+               }
+
+       }
+
+       return len;
+}
+
+
+/*
  * Parses a label from the given buffer.
  *
  * Returns a negative value on error, otherwise the amount of consumed
@@ -367,8 +434,10 @@ static const struct token tokens[] = {
        { T_LT,                 "<",     1 },
        { T_GT,                 ">",     1 },
        { T_EQ,                 "=",     1 },
+       { T_MATCH,              "~",     1 },
        { T_NOT,                "!",     1 },
        { T_WILDCARD,   "*",     1 },
+       { T_REGEXP,             "/",     1, parse_regexp },
        { T_STRING,             "'",     1, parse_string },
        { T_STRING,             "\"",    1, parse_string },
        { T_LABEL,              "_",     1, parse_label  },
@@ -378,7 +447,7 @@ static const struct token tokens[] = {
        { T_NUMBER,             "09",    0, parse_number },
 };
 
-const char *tokennames[23] = {
+const char *tokennames[25] = {
        [0]                             = "End of file",
        [T_AND]                 = "'&&'",
        [T_OR]                  = "'||'",
@@ -389,12 +458,14 @@ const char *tokennames[23] = {
        [T_GE]                  = "'>='",
        [T_LT]                  = "'<'",
        [T_LE]                  = "'<='",
+       [T_MATCH]       = "'~'",
        [T_NOT]                 = "'!'",
        [T_LABEL]               = "Label",
        [T_ROOT]                = "'$'",
        [T_THIS]                = "'@'",
        [T_DOT]                 = "'.'",
        [T_WILDCARD]    = "'*'",
+       [T_REGEXP]      = "/.../",
        [T_BROPEN]              = "'['",
        [T_BRCLOSE]             = "']'",
        [T_BOOL]                = "Bool",