xref: /netbsd-src/sys/external/bsd/acpica/dist/common/acgetline.c (revision 046a29855e04359424fd074e8313af6b6be8cfb6)
1 /******************************************************************************
2  *
3  * Module Name: acgetline - local line editing
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2023, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include "acpi.h"
45 #include "accommon.h"
46 #include "amlcode.h"
47 #include "acparser.h"
48 #include "acdebug.h"
49 
50 /*
51  * This is an os-independent implementation of line-editing services needed
52  * by the AcpiExec utility. It uses getchar() and putchar() and the existing
53  * history support provided by the AML debugger. It assumes that the terminal
54  * is in the correct line-editing mode such as raw and noecho. The OSL
55  * interface AcpiOsInitialize should do this. AcpiOsTerminate should put the
56  * terminal back into the original mode.
57  */
58 #define _COMPONENT          ACPI_OS_SERVICES
59         ACPI_MODULE_NAME    ("acgetline")
60 
61 
62 /* Local prototypes */
63 
64 static void
65 AcpiAcClearLine (
66     UINT32                  EndOfLine,
67     UINT32                  CursorPosition);
68 
69 /* Various ASCII constants */
70 
71 #define _ASCII_NUL                  0
72 #define _ASCII_BACKSPACE            0x08
73 #define _ASCII_TAB                  0x09
74 #define _ASCII_ESCAPE               0x1B
75 #define _ASCII_SPACE                0x20
76 #define _ASCII_LEFT_BRACKET         0x5B
77 #define _ASCII_DEL                  0x7F
78 #define _ASCII_UP_ARROW             'A'
79 #define _ASCII_DOWN_ARROW           'B'
80 #define _ASCII_RIGHT_ARROW          'C'
81 #define _ASCII_LEFT_ARROW           'D'
82 #define _ASCII_NEWLINE              '\n'
83 
84 /* Erase a single character on the input command line */
85 
86 #define ACPI_CLEAR_CHAR() \
87     putchar (_ASCII_BACKSPACE); \
88     putchar (_ASCII_SPACE); \
89     putchar (_ASCII_BACKSPACE);
90 
91 /* Backup cursor by Count positions */
92 
93 #define ACPI_BACKUP_CURSOR(i, Count) \
94     for (i = 0; i < (Count); i++) \
95         {putchar (_ASCII_BACKSPACE);}
96 
97 
98 /******************************************************************************
99  *
100  * FUNCTION:    AcpiAcClearLine
101  *
102  * PARAMETERS:  EndOfLine           - Current end-of-line index
103  *              CursorPosition      - Current cursor position within line
104  *
105  * RETURN:      None
106  *
107  * DESCRIPTION: Clear the entire command line the hard way, but probably the
108  *              most portable.
109  *
110  *****************************************************************************/
111 
112 static void
AcpiAcClearLine(UINT32 EndOfLine,UINT32 CursorPosition)113 AcpiAcClearLine (
114     UINT32                  EndOfLine,
115     UINT32                  CursorPosition)
116 {
117     UINT32                  i;
118 
119 
120     if (CursorPosition < EndOfLine)
121     {
122         /* Clear line from current position to end of line */
123 
124         for (i = 0; i < (EndOfLine - CursorPosition); i++)
125         {
126             putchar (' ');
127         }
128     }
129 
130     /* Clear the entire line */
131 
132     for (; EndOfLine > 0; EndOfLine--)
133     {
134         ACPI_CLEAR_CHAR ();
135     }
136 }
137 
138 
139 /******************************************************************************
140  *
141  * FUNCTION:    AcpiOsGetLine
142  *
143  * PARAMETERS:  Buffer              - Where to return the command line
144  *              BufferLength        - Maximum length of Buffer
145  *              BytesRead           - Where the actual byte count is returned
146  *
147  * RETURN:      Status and actual bytes read
148  *
149  * DESCRIPTION: Get the next input line from the terminal. NOTE: terminal
150  *              is expected to be in a mode that supports line-editing (raw,
151  *              noecho). This function is intended to be very portable. Also,
152  *              it uses the history support implemented in the AML debugger.
153  *
154  *****************************************************************************/
155 
156 ACPI_STATUS
AcpiOsGetLine(char * Buffer,UINT32 BufferLength,UINT32 * BytesRead)157 AcpiOsGetLine (
158     char                    *Buffer,
159     UINT32                  BufferLength,
160     UINT32                  *BytesRead)
161 {
162     char                    *NextCommand;
163     UINT32                  MaxCommandIndex = AcpiGbl_NextCmdNum - 1;
164     UINT32                  CurrentCommandIndex = MaxCommandIndex;
165     UINT32                  PreviousCommandIndex = MaxCommandIndex;
166     int                     InputChar;
167     UINT32                  CursorPosition = 0;
168     UINT32                  EndOfLine = 0;
169     UINT32                  i;
170 
171 
172     /* Always clear the line buffer before we read a new line */
173 
174     memset (Buffer, 0, BufferLength);
175 
176     /*
177      * This loop gets one character at a time (except for esc sequences)
178      * until a newline or error is detected.
179      *
180      * Note: Don't attempt to write terminal control ESC sequences, even
181      * though it makes certain things more difficult.
182      */
183     while (1)
184     {
185         if (EndOfLine >= (BufferLength - 1))
186         {
187             return (AE_BUFFER_OVERFLOW);
188         }
189 
190         InputChar = getchar ();
191         switch (InputChar)
192         {
193         default: /* This is the normal character case */
194 
195             /* Echo the character (at EOL) and copy it to the line buffer */
196 
197             if (EndOfLine == CursorPosition)
198             {
199                 putchar (InputChar);
200                 Buffer[EndOfLine] = (char) InputChar;
201 
202                 EndOfLine++;
203                 CursorPosition++;
204                 Buffer[EndOfLine] = 0;
205                 continue;
206             }
207 
208             /* Insert character into the middle of the buffer */
209 
210             memmove (&Buffer[CursorPosition + 1], &Buffer[CursorPosition],
211                 (EndOfLine - CursorPosition + 1));
212 
213             Buffer [CursorPosition] = (char) InputChar;
214             Buffer [EndOfLine + 1] = 0;
215 
216             /* Display the new part of line starting at the new character */
217 
218             fprintf (stdout, "%s", &Buffer[CursorPosition]);
219 
220             /* Restore cursor */
221 
222             ACPI_BACKUP_CURSOR (i, EndOfLine - CursorPosition);
223             CursorPosition++;
224             EndOfLine++;
225             continue;
226 
227         case _ASCII_DEL: /* Backspace key */
228 
229             if (!EndOfLine) /* Any characters on the command line? */
230             {
231                 continue;
232             }
233 
234             if (EndOfLine == CursorPosition) /* Erase the final character */
235             {
236                 ACPI_CLEAR_CHAR ();
237                 EndOfLine--;
238                 CursorPosition--;
239                 continue;
240             }
241 
242             if (!CursorPosition) /* Do not backup beyond start of line */
243             {
244                 continue;
245             }
246 
247             /* Remove the character from the line */
248 
249             memmove (&Buffer[CursorPosition - 1], &Buffer[CursorPosition],
250                 (EndOfLine - CursorPosition + 1));
251 
252             /* Display the new part of line starting at the new character */
253 
254             putchar (_ASCII_BACKSPACE);
255             fprintf (stdout, "%s ", &Buffer[CursorPosition - 1]);
256 
257             /* Restore cursor */
258 
259             ACPI_BACKUP_CURSOR (i, EndOfLine - CursorPosition + 1);
260             EndOfLine--;
261 
262             if (CursorPosition > 0)
263             {
264                 CursorPosition--;
265             }
266             continue;
267 
268         case _ASCII_NEWLINE: /* Normal exit case at end of command line */
269         case _ASCII_NUL:
270 
271             /* Return the number of bytes in the command line string */
272 
273             if (BytesRead)
274             {
275                 *BytesRead = EndOfLine;
276             }
277 
278             /* Echo, terminate string buffer, and exit */
279 
280             putchar (InputChar);
281             Buffer[EndOfLine] = 0;
282             return (AE_OK);
283 
284         case _ASCII_TAB:
285 
286             /* Ignore */
287 
288             continue;
289 
290         case EOF:
291 
292             return (AE_ERROR);
293 
294         case _ASCII_ESCAPE:
295 
296             /* Check for escape sequences of the form "ESC[x" */
297 
298             InputChar = getchar ();
299             if (InputChar != _ASCII_LEFT_BRACKET)
300             {
301                 continue; /* Ignore this ESC, does not have the '[' */
302             }
303 
304             /* Get the code following the ESC [ */
305 
306             InputChar = getchar (); /* Backup one character */
307             switch (InputChar)
308             {
309             case _ASCII_LEFT_ARROW:
310 
311                 if (CursorPosition > 0)
312                 {
313                     putchar (_ASCII_BACKSPACE);
314                     CursorPosition--;
315                 }
316                 continue;
317 
318             case _ASCII_RIGHT_ARROW:
319                 /*
320                  * Move one character forward. Do this without sending
321                  * ESC sequence to the terminal for max portability.
322                  */
323                 if (CursorPosition < EndOfLine)
324                 {
325                     /* Backup to start of line and print the entire line */
326 
327                     ACPI_BACKUP_CURSOR (i, CursorPosition);
328                     fprintf (stdout, "%s", Buffer);
329 
330                     /* Backup to where the cursor should be */
331 
332                     CursorPosition++;
333                     ACPI_BACKUP_CURSOR (i, EndOfLine - CursorPosition);
334                 }
335                 continue;
336 
337             case _ASCII_UP_ARROW:
338 
339                 /* If no commands available or at start of history list, ignore */
340 
341                 if (!CurrentCommandIndex)
342                 {
343                     continue;
344                 }
345 
346                 /* Manage our up/down progress */
347 
348                 if (CurrentCommandIndex > PreviousCommandIndex)
349                 {
350                     CurrentCommandIndex = PreviousCommandIndex;
351                 }
352 
353                 /* Get the historical command from the debugger */
354 
355                 NextCommand = AcpiDbGetHistoryByIndex (CurrentCommandIndex);
356                 if (!NextCommand)
357                 {
358                     return (AE_ERROR);
359                 }
360 
361                 /* Make this the active command and echo it */
362 
363                 AcpiAcClearLine (EndOfLine, CursorPosition);
364                 strcpy (Buffer, NextCommand);
365                 fprintf (stdout, "%s", Buffer);
366                 EndOfLine = CursorPosition = strlen (Buffer);
367 
368                 PreviousCommandIndex = CurrentCommandIndex;
369                 CurrentCommandIndex--;
370                 continue;
371 
372             case _ASCII_DOWN_ARROW:
373 
374                 if (!MaxCommandIndex) /* Any commands available? */
375                 {
376                     continue;
377                 }
378 
379                 /* Manage our up/down progress */
380 
381                 if (CurrentCommandIndex < PreviousCommandIndex)
382                 {
383                     CurrentCommandIndex = PreviousCommandIndex;
384                 }
385 
386                 /* If we are the end of the history list, output a clear new line */
387 
388                 if ((CurrentCommandIndex + 1) > MaxCommandIndex)
389                 {
390                     AcpiAcClearLine (EndOfLine, CursorPosition);
391                     EndOfLine = CursorPosition = 0;
392                     PreviousCommandIndex = CurrentCommandIndex;
393                     continue;
394                 }
395 
396                 PreviousCommandIndex = CurrentCommandIndex;
397                 CurrentCommandIndex++;
398 
399                  /* Get the historical command from the debugger */
400 
401                 NextCommand = AcpiDbGetHistoryByIndex (CurrentCommandIndex);
402                 if (!NextCommand)
403                 {
404                     return (AE_ERROR);
405                 }
406 
407                 /* Make this the active command and echo it */
408 
409                 AcpiAcClearLine (EndOfLine, CursorPosition);
410                 strcpy (Buffer, NextCommand);
411                 fprintf (stdout, "%s", Buffer);
412                 EndOfLine = CursorPosition = strlen (Buffer);
413                 continue;
414 
415             case 0x31:
416             case 0x32:
417             case 0x33:
418             case 0x34:
419             case 0x35:
420             case 0x36:
421                 /*
422                  * Ignore the various keys like insert/delete/home/end, etc.
423                  * But we must eat the final character of the ESC sequence.
424                  */
425                 (void) getchar ();
426                 continue;
427 
428             default:
429 
430                 /* Ignore random escape sequences that we don't care about */
431 
432                 continue;
433             }
434             continue;
435         }
436     }
437 }
438