1 /** @file
2 Write to an Interactive I/O Output device.
3
4 The functions assume that isatty() is TRUE at the time they are called.
5 Since the UEFI console is a WIDE character device, these functions do all
6 processing using wide characters.
7
8 It is the responsibility of the caller, or higher level function, to perform
9 any necessary translation between wide and narrow characters.
10
11 Copyright (c) 2012, Intel Corporation. All rights reserved.<BR>
12 This program and the accompanying materials are licensed and made available
13 under the terms and conditions of the BSD License which accompanies this
14 distribution. The full text of the license may be found at
15 http://opensource.org/licenses/bsd-license.php.
16
17 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
18 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
19 **/
20 #include <Uefi.h>
21
22 #include <LibConfig.h>
23
24 #include <assert.h>
25 #include <errno.h>
26 #include <sys/termios.h>
27 #include <Device/IIO.h>
28
29 static wchar_t Spaces[] = L" "; // Spaces for expanding TABs
30
31 #define MAX_TAB_WIDTH ((int)(sizeof(Spaces) / sizeof(wchar_t)) - 1)
32
33 #define MAX_EXPANSION 3
34
35 /** Process and buffer one character for output.
36
37 @param[in] filp Pointer to a file descriptor structure.
38 @param[out] OBuf Pointer to the Output Buffer FIFO.
39 @param[in] InCh The wide character to process.
40
41 @retval <0 An error occurred. Reason is in errno.
42 * EINVAL The pointer to the IIO object is NULL.
43 * ENOSPC The OBuf FIFO is full.
44
45 @retval 0 A character was input but not placed in the output buffer.
46
47 @retval >0 The number of characters buffered. Normally 1, or 2.
48 If a character is discarded because of flag settings, a
49 1 will be returned.
50 **/
51 ssize_t
IIO_WriteOne(struct __filedes * filp,cFIFO * OBuf,wchar_t InCh)52 IIO_WriteOne(struct __filedes *filp, cFIFO *OBuf, wchar_t InCh)
53 {
54 cIIO *This;
55 struct termios *Termio;
56 tcflag_t OFlag;
57 ssize_t RetVal;
58 wchar_t wc[MAX_EXPANSION]; // Sub-buffer for conversions
59 wchar_t *wcb; // Pointer to either wc or spaces
60 int numW = 0; // Wide characters placed in OBuf
61 INT32 TabWidth; // Each TAB expands into this number of spaces
62 UINT32 CurColumn; // Current cursor column on the screen
63 UINT32 CurRow; // Current cursor row on the screen
64 UINT32 PrevColumn; // Previous column. Used to detect wrapping.
65 UINT32 AdjColumn; // Current cursor column on the screen
66 UINT32 AdjRow; // Current cursor row on the screen
67
68 RetVal = -1;
69 wcb = wc;
70 This = filp->devdata;
71 if((This != NULL) && (OBuf->FreeSpace(OBuf, AsElements) >= MAX_EXPANSION)) {
72 Termio = &This->Termio;
73 OFlag = Termio->c_oflag;
74 TabWidth = (INT32)This->Termio.c_cc[VTABLEN];
75 if(TabWidth > MAX_TAB_WIDTH) {
76 TabWidth = MAX_TAB_WIDTH;
77 }
78 CurColumn = This->CurrentXY.Column;
79 CurRow = This->CurrentXY.Row;
80
81 numW = 1; // The majority of characters buffer one character
82 AdjRow = 0; // Most characters just cause horizontal movement
83 AdjColumn = 0;
84 if(OFlag & OPOST) {
85 /* Perform output processing */
86 switch(InCh) {
87 case CHAR_TAB: //{{
88 if(OFlag & OXTABS) {
89 if(TabWidth > 0) {
90 int SpaceIndex;
91
92 SpaceIndex = CurColumn % TabWidth; // Number of spaces after a Tab Stop
93 numW = TabWidth - SpaceIndex; // Number of spaces to the next Tab Stop
94 SpaceIndex = MAX_TAB_WIDTH - numW; // Index into the Spaces array
95 wcb = &Spaces[SpaceIndex]; // Point to the appropriate number of spaces
96 }
97 else {
98 wc[0] = L' ';
99 }
100 AdjColumn = numW;
101 }
102 else {
103 wc[0] = InCh; // Send the TAB itself - assumes that it does not move cursor.
104 }
105 break; //}}
106
107 case CHAR_CARRIAGE_RETURN: //{{
108 if((OFlag & OCRNL) == 0) {
109 if((OFlag & ONLRET) == 0) {
110 numW = 0; /* Discard the CR */
111 // Cursor doesn't move
112 }
113 else {
114 wc[0] = CHAR_CARRIAGE_RETURN;
115 CurColumn = 0;
116 }
117 break;
118 }
119 else {
120 InCh = CHAR_LINEFEED;
121 } //}}
122 // Fall through to the NL case
123 case CHAR_LINEFEED: //{{
124 if(OFlag & ONLCR) {
125 wc[0] = CHAR_CARRIAGE_RETURN;
126 wc[1] = CHAR_LINEFEED;
127 numW = 2;
128 CurColumn = 0;
129 }
130 AdjRow = 1;
131 break; //}}
132
133 case CHAR_BACKSPACE: //{{
134 if(CurColumn > 0) {
135 wc[0] = CHAR_BACKSPACE;
136 CurColumn = (UINT32)ModuloDecrement(CurColumn, (UINT32)This->MaxColumn);
137 }
138 else {
139 numW = 0; // Discard the backspace if in column 0
140 }
141 break; //}}
142
143 case CHAR_EOT: //{{
144 if(OFlag & ONOEOT) {
145 numW = 0; // Discard the EOT character
146 // Cursor doesn't move
147 break;
148 } //}}
149 // Fall through to default in order to potentially output "^D"
150 default: //{{
151 if((InCh >= 0) && (InCh < L' ')) {
152 // InCh contains a control character
153 if(OFlag & OCTRL) {
154 wc[1] = InCh + L'@';
155 wc[0] = L'^';
156 numW = 2;
157 AdjColumn = 2;
158 }
159 else {
160 numW = 0; // Discard. Not a UEFI supported control character.
161 }
162 }
163 else {
164 // Regular printing character
165 wc[0] = InCh;
166 AdjColumn = 1;
167 }
168 break; //}}
169 }
170 if(numW < MAX_EXPANSION) {
171 wc[numW] = 0; // Terminate the sub-buffer
172 }
173 if(AdjColumn != 0) {
174 // Adjust the cursor position
175 PrevColumn = CurColumn;
176 CurColumn = ModuloAdd(PrevColumn, AdjColumn, (UINT32)This->MaxColumn);
177 if(CurColumn < PrevColumn) {
178 // We must have wrapped, so we are on the next Row
179 ++CurRow;
180 if(CurRow >= This->MaxRow) {
181 // The screen has scrolled so need to adjust Initial location.
182 --This->InitialXY.Row; // Initial row has moved up one
183 CurRow = (UINT32)(This->MaxRow - 1); // We stay on the bottom row
184 }
185 }
186 }
187 This->CurrentXY.Column = CurColumn;
188 This->CurrentXY.Row = CurRow;
189 }
190 else {
191 // Output processing disabled -- RAW output mode
192 wc[0] = InCh;
193 wc[1] = 0;
194 }
195 // Put the character(s) into the output buffer
196 if(numW > 0) {
197 (void)OBuf->Write(OBuf, (const void *)wcb, (size_t)numW);
198 }
199 RetVal = numW;
200 }
201 else {
202 if(This == NULL) {
203 errno = EINVAL;
204 }
205 else {
206 errno = ENOSPC;
207 }
208 }
209 return RetVal;
210 }
211