1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
//Types of ANSI Escape Sequences
//C0 [0x07-0x0A|0x0C-0x0D|0x1B]
//C1/Fe [ESC][0x40-0x5F]
// technically can be represented in 1 byte w/ bytes above 0x80 but
// unimplemented b/c of unicode
// STring Terminator ESC \
//CSI (ESC\[|0x9B)[0-9:;<=>?]*[!"#$%&'()*+,-./]*[&A-Z[\]^_`a-z{|}~]
//OSC (ESC\]|0x9D).*(0x9C|0x1B 0x5C)
//OCS (ESCP|0x90).*(0x9C|0x1B 0x5C)
//Fs ESC[0x60-0x7E]
//nF ESC[0x20-02F]*[0x30-0x7E]
//Fp ESC[0x30-0x3F] save and clear
//Clearing commands
//ESC c
//ESC [ [1-3] J
//ESC [ [1-2] K
//ESC [ m @
// note: these two can't clear im preview b/c of scroll locking
//last read key
enum esc_state {
//C0 except BEL or ESC, \n ,\r and \f
C0,
ESC,
CSI_START,
CSI_MID,
CSI_END,
//OSC, DCS, PM APC etc ST terminted C1,
C1_START,
ST,
nF_START,
nF_END,
//other fixed elngth C1, Fs,
C1,
//save and clear
DECSC,
DECRC,
NORMAL,
//escape followed by an escape, has to be user generated
DOUBLE_ESC,
};
//returns 1 if the current state is safe to insert characters after, 0 if not
int safe_state(enum esc_state state) {
switch (state) {
case CSI_END:
case ST:
case nF_END:
case C0:
case C1:
case DECSC:
case DECRC:
case DOUBLE_ESC:
case NORMAL:
return 1;
break;
default:
return 0;
break;
}
}
//global stdin -> pty ESC state
enum esc_state in_state = NORMAL;
//global pty -> stdout ESC state
enum esc_state out_state = NORMAL;
//global output parity
int out_c_parity = 0;
//global output clear state, cleared by im_routine_update
int out_clr = 0;
//updates the state, the return is the type of the last character read
//updates c parity depending on cursor store and restore
//if c parity is not NULL
//sets clr to 1 if it encounters a cursor clear escape sequence
// if clr is not NULL
enum esc_state update_esc_state(char * buff,unsigned int buff_len,
enum esc_state state,
int * c_parity, int * clr)
{
for (int i = 0; i < buff_len; i++) {
char c = buff[i];
switch (state) {
case CSI_END:
case ST:
case nF_END:
case C0:
case C1:
case DECSC:
case DECRC:
case DOUBLE_ESC:
//all the sequences that have ended don't have an end
//and default to normal
case NORMAL:
if (c >= 0x08 && c <= 0x0A) {
state = C0;
}
if (c == 0x1B) {
state = ESC;
} else {
//return to normal
state = NORMAL;
}
break;
case ESC:
if (c == 'c') {
if (clr != NULL) {
*clr = 1;
}
}
//fix length C1
else if (c == 'N' || c == 'O') {
state = C1;
}
else if (c == '[') {
state = CSI_START;
}
//ST terminated C1 OSC, DCS, SOS, PM, APC
else if (c == ']' || c =='P' || c == '^' || c == 'X' || c == '_') {
state = C1_START;
}
else if (c == '\\') {
state - ST;
}
else if (c == '7') {
state = DECSC;
if ( c_parity != NULL) {
*c_parity++;
}
}
else if (c == '8') {
state = DECRC;
if ( c_parity != NULL) {
*c_parity--;
}
}
//nF
else if (c >= 0x20 && c <= 0x2F) {
state = nF_START;
}
//all other Fe/C1 Sequences, should be fixed len
else if (c >= 0x40 && c <= 0x5F) {
state = C1;
}
//Fs Sequences
else if (c >= 0x60 && c <= 0x7E) {
state = C1;
}
else if (c == 0x1B) {
state = DOUBLE_ESC;
//deformed escape sequence
}
else {
state = NORMAL;
}
break;
case C1_START:
if (c == 0x1B) {
state = ESC;
}
if (c == 0x9C) {
state = ST;
}
break;
case CSI_START:
case CSI_MID:
if (c == 'J') {
state = CSI_END;
if (clr != NULL) {
*clr = 1;
}
} else if (c >= 0x30 && c <= 0x3F) {
state = CSI_MID;
} else if (c >= 0x20 && c <= 0x2F) {
state = CSI_MID;
} else if (c >= 0x40 && c <= 0x7E) {
state = CSI_END;
} else {
//malformed CSI sequence
state = NORMAL;
}
break;
case nF_START:
if (c >= 0x20 && c <= 0x2F) {
state = nF_START;
} else if (c >= 0x30 && c <= 0x7E) {
state = nF_END;
//malformed nF sequence
} else {
state = NORMAL;
}
break;
}
}
return state;
}
|
