1 // Scintilla source code edit control
2 /** @file LexAsn1.cxx
3  ** Lexer for ASN.1
4  **/
5 // Copyright 2004 by Herr Pfarrer rpfarrer <at> yahoo <dot> de
6 // Last Updated: 20/07/2004
7 // The License.txt file describes the conditions under which this software may be distributed.
8 
9 #include <stdlib.h>
10 #include <string.h>
11 #include <stdio.h>
12 #include <stdarg.h>
13 #include <assert.h>
14 
15 #include "ILexer.h"
16 #include "Scintilla.h"
17 #include "SciLexer.h"
18 
19 #include "WordList.h"
20 #include "LexAccessor.h"
21 #include "Accessor.h"
22 #include "StyleContext.h"
23 #include "CharacterSet.h"
24 #include "LexerModule.h"
25 
26 using namespace Scintilla;
27 
28 // Some char test functions
isAsn1Number(int ch)29 static bool isAsn1Number(int ch)
30 {
31 	return (ch >= '0' && ch <= '9');
32 }
33 
isAsn1Letter(int ch)34 static bool isAsn1Letter(int ch)
35 {
36 	return (ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z');
37 }
38 
isAsn1Char(int ch)39 static bool isAsn1Char(int ch)
40 {
41 	return (ch == '-' ) || isAsn1Number(ch) || isAsn1Letter (ch);
42 }
43 
44 //
45 //	Function determining the color of a given code portion
46 //	Based on a "state"
47 //
ColouriseAsn1Doc(Sci_PositionU startPos,Sci_Position length,int initStyle,WordList * keywordLists[],Accessor & styler)48 static void ColouriseAsn1Doc(Sci_PositionU startPos, Sci_Position length, int initStyle, WordList *keywordLists[], Accessor &styler)
49 {
50 	// The keywords
51 	WordList &Keywords = *keywordLists[0];
52 	WordList &Attributes = *keywordLists[1];
53 	WordList &Descriptors = *keywordLists[2];
54 	WordList &Types = *keywordLists[3];
55 
56 	// Parse the whole buffer character by character using StyleContext
57 	StyleContext sc(startPos, length, initStyle, styler);
58 	for (; sc.More(); sc.Forward())
59 	{
60 		// The state engine
61 		switch (sc.state)
62 		{
63 		case SCE_ASN1_DEFAULT:		// Plain characters
64 asn1_default:
65 			if (sc.ch == '-' && sc.chNext == '-')
66 				// A comment begins here
67 				sc.SetState(SCE_ASN1_COMMENT);
68 			else if (sc.ch == '"')
69 				// A string begins here
70 				sc.SetState(SCE_ASN1_STRING);
71 			else if (isAsn1Number (sc.ch))
72 				// A number starts here (identifier should start with a letter in ASN.1)
73 				sc.SetState(SCE_ASN1_SCALAR);
74 			else if (isAsn1Char (sc.ch))
75 				// An identifier starts here (identifier always start with a letter)
76 				sc.SetState(SCE_ASN1_IDENTIFIER);
77 			else if (sc.ch == ':')
78 				// A ::= operator starts here
79 				sc.SetState(SCE_ASN1_OPERATOR);
80 			break;
81 		case SCE_ASN1_COMMENT:		// A comment
82 			if (sc.ch == '\r' || sc.ch == '\n')
83 				// A comment ends here
84 				sc.SetState(SCE_ASN1_DEFAULT);
85 			break;
86 		case SCE_ASN1_IDENTIFIER:	// An identifier (keyword, attribute, descriptor or type)
87 			if (!isAsn1Char (sc.ch))
88 			{
89 				// The end of identifier is here: we can look for it in lists by now and change its state
90 				char s[100];
91 				sc.GetCurrent(s, sizeof(s));
92 				if (Keywords.InList(s))
93 					// It's a keyword, change its state
94 					sc.ChangeState(SCE_ASN1_KEYWORD);
95 				else if (Attributes.InList(s))
96 					// It's an attribute, change its state
97 					sc.ChangeState(SCE_ASN1_ATTRIBUTE);
98 				else if (Descriptors.InList(s))
99 					// It's a descriptor, change its state
100 					sc.ChangeState(SCE_ASN1_DESCRIPTOR);
101 				else if (Types.InList(s))
102 					// It's a type, change its state
103 					sc.ChangeState(SCE_ASN1_TYPE);
104 
105 				// Set to default now
106 				sc.SetState(SCE_ASN1_DEFAULT);
107 			}
108 			break;
109 		case SCE_ASN1_STRING:		// A string delimited by ""
110 			if (sc.ch == '"')
111 			{
112 				// A string ends here
113 				sc.ForwardSetState(SCE_ASN1_DEFAULT);
114 
115 				// To correctly manage a char sticking to the string quote
116 				goto asn1_default;
117 			}
118 			break;
119 		case SCE_ASN1_SCALAR:		// A plain number
120 			if (!isAsn1Number (sc.ch))
121 				// A number ends here
122 				sc.SetState(SCE_ASN1_DEFAULT);
123 			break;
124 		case SCE_ASN1_OPERATOR:		// The affectation operator ::= and wath follows (eg: ::= { org 6 } OID or ::= 12 trap)
125 			if (sc.ch == '{')
126 			{
127 				// An OID definition starts here: enter the sub loop
128 				for (; sc.More(); sc.Forward())
129 				{
130 					if (isAsn1Number (sc.ch) && (!isAsn1Char (sc.chPrev) || isAsn1Number (sc.chPrev)))
131 						// The OID number is highlighted
132 						sc.SetState(SCE_ASN1_OID);
133 					else if (isAsn1Char (sc.ch))
134 						// The OID parent identifier is plain
135 						sc.SetState(SCE_ASN1_IDENTIFIER);
136 					else
137 						sc.SetState(SCE_ASN1_DEFAULT);
138 
139 					if (sc.ch == '}')
140 						// Here ends the OID and the operator sub loop: go back to main loop
141 						break;
142 				}
143 			}
144 			else if (isAsn1Number (sc.ch))
145 			{
146 				// A trap number definition starts here: enter the sub loop
147 				for (; sc.More(); sc.Forward())
148 				{
149 					if (isAsn1Number (sc.ch))
150 						// The trap number is highlighted
151 						sc.SetState(SCE_ASN1_OID);
152 					else
153 					{
154 						// The number ends here: go back to main loop
155 						sc.SetState(SCE_ASN1_DEFAULT);
156 						break;
157 					}
158 				}
159 			}
160 			else if (sc.ch != ':' && sc.ch != '=' && sc.ch != ' ')
161 				// The operator doesn't imply an OID definition nor a trap, back to main loop
162 				goto asn1_default; // To be sure to handle actually the state change
163 			break;
164 		}
165 	}
166 	sc.Complete();
167 }
168 
FoldAsn1Doc(Sci_PositionU,Sci_Position,int,WordList * [],Accessor & styler)169 static void FoldAsn1Doc(Sci_PositionU, Sci_Position, int, WordList *[], Accessor &styler)
170 {
171 	// No folding enabled, no reason to continue...
172 	if( styler.GetPropertyInt("fold") == 0 )
173 		return;
174 
175 	// No folding implemented: doesn't make sense for ASN.1
176 }
177 
178 static const char * const asn1WordLists[] = {
179 	"Keywords",
180 	"Attributes",
181 	"Descriptors",
182 	"Types",
183 	0, };
184 
185 
186 LexerModule lmAsn1(SCLEX_ASN1, ColouriseAsn1Doc, "asn1", FoldAsn1Doc, asn1WordLists);
187