1 /** @file
2 Canonical Interactive Input Function.
3
4 The functions assume that isatty() is TRUE at the time they are called.
5
6 Copyright (c) 2012 - 2014, Intel Corporation. All rights reserved.<BR>
7 This program and the accompanying materials are licensed and made available
8 under the terms and conditions of the BSD License which accompanies this
9 distribution. The full text of the license may be found at
10 http://opensource.org/licenses/bsd-license.php.
11
12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
14 **/
15 #include <Uefi.h>
16
17 #include <LibConfig.h>
18
19 #include <errno.h>
20 #include <sys/syslimits.h>
21 #include <sys/termios.h>
22 #include <Device/IIO.h>
23 #include <MainData.h>
24 #include "IIOutilities.h"
25 #include "IIOechoCtrl.h"
26
27 /** Read a line from the input file in canonical mode.
28 Perform echoing and input processing as directed by the termios flags.
29
30 @param[in] filp A pointer to a file descriptor structure.
31
32 @return The number of characters in the input buffer, or -1 if there
33 was an error.
34 **/
35 ssize_t
IIO_CanonRead(struct __filedes * filp)36 IIO_CanonRead (
37 struct __filedes *filp
38 )
39 {
40 cIIO *This;
41 cFIFO *InBuf;
42 struct termios *Termio;
43 struct __filedes *fpOut;
44 size_t NumRead;
45 wint_t InChar;
46 tcflag_t IFlag;
47 tcflag_t LFlag;
48 BOOLEAN EchoIsOK;
49 BOOLEAN Activate;
50 BOOLEAN FirstRead;
51 int OutMode;
52 UINTN MaxColumn;
53 UINTN MaxRow;
54
55 NumRead = MAX_INPUT; // Workaround "potentially uninitialized" warning
56 EchoIsOK = FALSE;
57 FirstRead = TRUE;
58 This = filp->devdata;
59 Termio = &This->Termio;
60 InBuf = This->InBuf;
61
62 // Get a copy of the flags we are going to use
63 IFlag = Termio->c_iflag;
64 LFlag = Termio->c_lflag;
65
66 /* Determine what the current screen size is. Also validates the output device. */
67 OutMode = IIO_GetOutputSize(STDOUT_FILENO, &MaxColumn, &MaxRow);
68 if(OutMode >= 0) {
69 /* Set the maximum screen dimensions. */
70 This->MaxColumn = MaxColumn;
71 This->MaxRow = MaxRow;
72
73 /* Record where the cursor is at the beginning of this Input operation.
74 The currently set stdout device is used to determine this. If there is
75 no stdout, or stdout is not an interactive device, nothing is recorded.
76 */
77 if (IIO_GetCursorPosition(STDOUT_FILENO, &This->InitialXY.Column, &This->InitialXY.Row) >= 0) {
78 This->CurrentXY.Column = This->InitialXY.Column;
79 This->CurrentXY.Row = This->InitialXY.Row;
80 EchoIsOK = TRUE; // Can only echo to stdout
81 }
82 }
83
84 // For now, we only echo to stdout.
85 fpOut = &gMD->fdarray[STDOUT_FILENO];
86
87 // Input and process characters until BufferSize is exhausted.
88 do {
89 InChar = IIO_GetInChar(filp, FirstRead);
90 if (InChar == WEOF) {
91 NumRead = 0;
92 break;
93 }
94 FirstRead = FALSE;
95 Activate = TRUE;
96 if(InChar == CHAR_CARRIAGE_RETURN) {
97 if((IFlag & IGNCR) != 0) {
98 continue; // Restart the do loop, discarding the CR
99 }
100 else if((IFlag & ICRNL) != 0) {
101 InChar = L'\n';
102 }
103 }
104 else if(InChar == CHAR_LINEFEED) {
105 if((IFlag & INLCR) != 0) {
106 InChar = L'\r';
107 }
108 }
109 else if(CCEQ(Termio->c_cc[VINTR], InChar)) {
110 if((LFlag & ISIG) != 0) {
111 // Raise Signal
112 // Flush Input Buffer
113 // Return to caller
114 InChar = IIO_ECHO_DISCARD;
115 errno = EINTR;
116 }
117 else {
118 Activate = FALSE;
119 }
120 }
121 else if(CCEQ(Termio->c_cc[VQUIT], InChar)) {
122 if((LFlag & ISIG) != 0) {
123 // Raise Signal
124 // Flush Input Buffer
125 // Return to caller
126 InChar = IIO_ECHO_DISCARD;
127 errno = EINTR;
128 }
129 else {
130 Activate = FALSE;
131 }
132 }
133 else if(CCEQ(Termio->c_cc[VEOF], InChar)) {
134 InChar = WEOF;
135 NumRead = 0;
136 EchoIsOK = FALSE; // Buffer, but don't echo this character
137 }
138 else if(CCEQ(Termio->c_cc[VEOL], InChar)) {
139 EchoIsOK = FALSE; // Buffer, but don't echo this character
140 }
141 else if(CCEQ(Termio->c_cc[VERASE], InChar)) {
142 InChar = IIO_ECHO_ERASE;
143 Activate = FALSE;
144 }
145 else if(CCEQ(Termio->c_cc[VKILL], InChar)) {
146 InChar = IIO_ECHO_KILL;
147 Activate = FALSE;
148 }
149 else {
150 if((InChar < TtySpecKeyMin) || (InChar >= TtyFunKeyMax)) {
151 Activate = FALSE;
152 }
153 }
154 /** The Echo function is responsible for:
155 * Adding the character to the input buffer, if appropriate.
156 * Removing characters from the input buffer for ERASE and KILL processing.
157 * Visually removing characters from the screen if ECHOE is set.
158 * Ensuring one can not backspace beyond the beginning of the input text.
159 * Sending final echo strings to output.
160 **/
161 (void)This->Echo(fpOut, (wchar_t)InChar, EchoIsOK);
162 NumRead = InBuf->Count(InBuf, AsElements);
163 } while((NumRead < MAX_INPUT) &&
164 (Activate == FALSE));
165
166 return (ssize_t)NumRead;
167 }
168