iPXE
editstring.c
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1 /*
2  * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of the
7  * License, or any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA.
18  *
19  * You can also choose to distribute this program under the terms of
20  * the Unmodified Binary Distribution Licence (as given in the file
21  * COPYING.UBDL), provided that you have satisfied its requirements.
22  */
23 
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25 
26 #include <assert.h>
27 #include <string.h>
28 #include <ctype.h>
29 #include <ipxe/keys.h>
30 #include <ipxe/editstring.h>
31 
32 /** @file
33  *
34  * Editable strings
35  *
36  */
37 
38 static void insert_delete ( struct edit_string *string, size_t delete_len,
39  const char *insert_text )
40  __attribute__ (( nonnull (1) ));
41 static void insert_character ( struct edit_string *string,
42  unsigned int character ) __nonnull;
43 static void delete_character ( struct edit_string *string ) __nonnull;
44 static void backspace ( struct edit_string *string ) __nonnull;
45 static void previous_word ( struct edit_string *string ) __nonnull;
46 static void kill_word ( struct edit_string *string ) __nonnull;
47 static void kill_sol ( struct edit_string *string ) __nonnull;
48 static void kill_eol ( struct edit_string *string ) __nonnull;
49 
50 /**
51  * Insert and/or delete text within an editable string
52  *
53  * @v string Editable string
54  * @v delete_len Length of text to delete from current cursor position
55  * @v insert_text Text to insert at current cursor position, or NULL
56  */
57 static void insert_delete ( struct edit_string *string, size_t delete_len,
58  const char *insert_text ) {
59  size_t old_len, max_delete_len, insert_len, max_insert_len, new_len;
60 
61  /* Calculate lengths */
62  old_len = strlen ( string->buf );
63  assert ( string->cursor <= old_len );
64  max_delete_len = ( old_len - string->cursor );
65  if ( delete_len > max_delete_len )
66  delete_len = max_delete_len;
67  insert_len = ( insert_text ? strlen ( insert_text ) : 0 );
68  max_insert_len = ( ( string->len - 1 ) - ( old_len - delete_len ) );
69  if ( insert_len > max_insert_len )
70  insert_len = max_insert_len;
71  new_len = ( old_len - delete_len + insert_len );
72 
73  /* Fill in edit history */
74  string->mod_start = string->cursor;
75  string->mod_end = ( ( new_len > old_len ) ? new_len : old_len );
76 
77  /* Move data following the cursor */
78  memmove ( ( string->buf + string->cursor + insert_len ),
79  ( string->buf + string->cursor + delete_len ),
80  ( max_delete_len + 1 - delete_len ) );
81 
82  /* Copy inserted text to cursor position */
83  memcpy ( ( string->buf + string->cursor ), insert_text, insert_len );
84  string->cursor += insert_len;
85 }
86 
87 /**
88  * Insert character at current cursor position
89  *
90  * @v string Editable string
91  * @v character Character to insert
92  */
93 static void insert_character ( struct edit_string *string,
94  unsigned int character ) {
95  char insert_text[2] = { character, '\0' };
96  insert_delete ( string, 0, insert_text );
97 }
98 
99 /**
100  * Delete character at current cursor position
101  *
102  * @v string Editable string
103  */
104 static void delete_character ( struct edit_string *string ) {
105  insert_delete ( string, 1, NULL );
106 }
107 
108 /**
109  * Delete character to left of current cursor position
110  *
111  * @v string Editable string
112  */
113 static void backspace ( struct edit_string *string ) {
114  if ( string->cursor > 0 ) {
115  string->cursor--;
116  delete_character ( string );
117  }
118 }
119 
120 /**
121  * Move to start of previous word
122  *
123  * @v string Editable string
124  */
125 static void previous_word ( struct edit_string *string ) {
126  while ( string->cursor &&
127  isspace ( string->buf[ string->cursor - 1 ] ) ) {
128  string->cursor--;
129  }
130  while ( string->cursor &&
131  ( ! isspace ( string->buf[ string->cursor - 1 ] ) ) ) {
132  string->cursor--;
133  }
134 }
135 
136 /**
137  * Delete to end of previous word
138  *
139  * @v string Editable string
140  */
141 static void kill_word ( struct edit_string *string ) {
142  size_t old_cursor = string->cursor;
143  previous_word ( string );
144  insert_delete ( string, ( old_cursor - string->cursor ), NULL );
145 }
146 
147 /**
148  * Delete to start of line
149  *
150  * @v string Editable string
151  */
152 static void kill_sol ( struct edit_string *string ) {
153  size_t old_cursor = string->cursor;
154  string->cursor = 0;
155  insert_delete ( string, old_cursor, NULL );
156 }
157 
158 /**
159  * Delete to end of line
160  *
161  * @v string Editable string
162  */
163 static void kill_eol ( struct edit_string *string ) {
164  insert_delete ( string, ~( ( size_t ) 0 ), NULL );
165 }
166 
167 /**
168  * Replace editable string
169  *
170  * @v string Editable string
171  * @v replacement Replacement string
172  */
173 void replace_string ( struct edit_string *string, const char *replacement ) {
174  string->cursor = 0;
175  insert_delete ( string, ~( ( size_t ) 0 ), replacement );
176 }
177 
178 /**
179  * Edit editable string
180  *
181  * @v string Editable string
182  * @v key Key pressed by user
183  * @ret key Key returned to application, or zero
184  *
185  * Handles keypresses and updates the content of the editable string.
186  * Basic line editing facilities (delete/insert/cursor) are supported.
187  * If edit_string() understands and uses the keypress it will return
188  * zero, otherwise it will return the original key.
189  *
190  * This function does not update the display in any way.
191  *
192  * The string's edit history will be updated to allow the caller to
193  * efficiently bring the display into sync with the string content.
194  */
195 int edit_string ( struct edit_string *string, int key ) {
196  int retval = 0;
197  size_t len = strlen ( string->buf );
198 
199  /* Prepare edit history */
200  string->last_cursor = string->cursor;
201  string->mod_start = string->cursor;
202  string->mod_end = string->cursor;
203 
204  /* Interpret key */
205  if ( ( key >= 0x20 ) && ( key <= 0x7e ) ) {
206  /* Printable character; insert at current position */
207  insert_character ( string, key );
208  } else switch ( key ) {
209  case KEY_BACKSPACE:
210  /* Backspace */
211  backspace ( string );
212  break;
213  case KEY_DC:
214  case CTRL_D:
215  /* Delete character */
216  delete_character ( string );
217  break;
218  case CTRL_W:
219  /* Delete word */
220  kill_word ( string );
221  break;
222  case CTRL_U:
223  /* Delete to start of line */
224  kill_sol ( string );
225  break;
226  case CTRL_K:
227  /* Delete to end of line */
228  kill_eol ( string );
229  break;
230  case KEY_HOME:
231  case CTRL_A:
232  /* Start of line */
233  string->cursor = 0;
234  break;
235  case KEY_END:
236  case CTRL_E:
237  /* End of line */
238  string->cursor = len;
239  break;
240  case KEY_LEFT:
241  case CTRL_B:
242  /* Cursor left */
243  if ( string->cursor > 0 )
244  string->cursor--;
245  break;
246  case KEY_RIGHT:
247  case CTRL_F:
248  /* Cursor right */
249  if ( string->cursor < len )
250  string->cursor++;
251  break;
252  default:
253  retval = key;
254  break;
255  }
256 
257  return retval;
258 }
#define CTRL_B
Definition: keys.h:19
Editable strings.
#define __attribute__(x)
Definition: compiler.h:10
#define CTRL_E
Definition: keys.h:22
void replace_string(struct edit_string *string, const char *replacement)
Replace editable string.
Definition: editstring.c:173
int edit_string(struct edit_string *string, int key)
Edit editable string.
Definition: editstring.c:195
uint32_t string
Definition: multiboot.h:14
Character types.
#define KEY_HOME
Home.
Definition: keys.h:70
static void backspace(struct edit_string *string) __nonnull
Delete character to left of current cursor position.
Definition: editstring.c:113
#define __nonnull
Declare a function's pointer parameters as non-null - i.e.
Definition: compiler.h:592
void * memcpy(void *dest, const void *src, size_t len) __nonnull
#define CTRL_K
Definition: keys.h:28
Assertions.
assert((readw(&hdr->flags) &(GTF_reading|GTF_writing))==0)
int isspace(int character)
Check to see if character is a space.
Definition: ctype.c:41
#define CTRL_W
Definition: keys.h:40
#define KEY_END
End.
Definition: keys.h:69
size_t strlen(const char *src)
Get length of string.
Definition: string.c:228
#define CTRL_F
Definition: keys.h:23
static void insert_character(struct edit_string *string, unsigned int character) __nonnull
Insert character at current cursor position.
Definition: editstring.c:93
void * memmove(void *dest, const void *src, size_t len) __nonnull
#define CTRL_A
Definition: keys.h:18
#define CTRL_U
Definition: keys.h:38
static void kill_eol(struct edit_string *string) __nonnull
Delete to end of line.
Definition: editstring.c:163
unsigned long retval
Definition: xen.h:45
#define KEY_DC
Delete.
Definition: keys.h:72
static void kill_sol(struct edit_string *string) __nonnull
Delete to start of line.
Definition: editstring.c:152
FILE_LICENCE(GPL2_OR_LATER_OR_UBDL)
uint32_t len
Length.
Definition: ena.h:14
Key definitions.
An editable string.
Definition: editstring.h:13
#define KEY_RIGHT
Right arrow.
Definition: keys.h:67
static void insert_delete(struct edit_string *string, size_t delete_len, const char *insert_text) __attribute__((nonnull(1)))
Insert and/or delete text within an editable string.
Definition: editstring.c:57
#define CTRL_D
Definition: keys.h:21
#define KEY_BACKSPACE
Definition: keys.h:87
static void kill_word(struct edit_string *string) __nonnull
Delete to end of previous word.
Definition: editstring.c:141
#define NULL
NULL pointer (VOID *)
Definition: Base.h:362
String functions.
static void previous_word(struct edit_string *string) __nonnull
Move to start of previous word.
Definition: editstring.c:125
#define KEY_LEFT
Left arrow.
Definition: keys.h:68
union @375 key
Sense key.
Definition: scsi.h:18
static void delete_character(struct edit_string *string) __nonnull
Delete character at current cursor position.
Definition: editstring.c:104