[CMD] Fix Coverity #715934 "Copy-paste error" (#1040)
[reactos.git] / base / shell / cmd / history.c
1 /*
2 * HISTORY.C - command line history.
3 *
4 *
5 * History:
6 *
7 * 14/01/95 (Tim Norman)
8 * started.
9 *
10 * 08/08/95 (Matt Rains)
11 * i have cleaned up the source code. changes now bring this source
12 * into guidelines for recommended programming practice.
13 *
14 * 27-Jul-1998 (John P Price <linux-guru@gcfl.net>)
15 * added config.h include
16 *
17 * 25-Jan-1999 (Eric Kohl)
18 * Cleanup!
19 * Unicode and redirection safe!
20 *
21 * 25-Jan-1999 (Paolo Pantaleo <paolopan@freemail.it>)
22 * Added lots of comments (beginning studying the source)
23 * Added command.com's F3 support (see cmdinput.c)
24 *
25 */
26
27
28
29 /*
30 * HISTORY.C - command line history. Second version
31 *
32 *
33 * History:
34 *
35 * 06/12/99 (Paolo Pantaleo <paolopan@freemail.it>)
36 * started.
37 *
38 */
39
40 #include "precomp.h"
41
42 #ifdef FEATURE_HISTORY
43
44 typedef struct tagHISTORY
45 {
46 struct tagHISTORY *prev;
47 struct tagHISTORY *next;
48 LPTSTR string;
49 } HIST_ENTRY, * LPHIST_ENTRY;
50
51 static INT size, max_size = 100;
52
53 static LPHIST_ENTRY Top = NULL;
54 static LPHIST_ENTRY Bottom = NULL;
55
56 static LPHIST_ENTRY curr_ptr = NULL;
57
58 VOID InitHistory(VOID);
59 VOID History_move_to_bottom(VOID);
60 VOID History(INT dir, LPTSTR commandline);
61 VOID CleanHistory(VOID);
62 VOID History_del_current_entry(LPTSTR str);
63
64 /*service functions*/
65 static VOID del(LPHIST_ENTRY item);
66 static VOID add_at_bottom(LPTSTR string);
67 /*VOID add_before_last(LPTSTR string);*/
68 VOID set_size(INT new_size);
69
70
71 INT CommandHistory(LPTSTR param)
72 {
73 LPTSTR tmp;
74 INT tmp_int;
75 LPHIST_ENTRY h_tmp;
76 TCHAR szBuffer[2048];
77
78 tmp=_tcschr(param,_T('/'));
79
80 if (tmp)
81 {
82 param=tmp;
83 switch (_totupper(param[1]))
84 {
85 case _T('F'):/*delete history*/
86 CleanHistory();InitHistory();
87 break;
88
89 case _T('R'):/*read history from standard in*/
90 for(;;)
91 {
92 ConInString(szBuffer,sizeof(szBuffer)/sizeof(TCHAR));
93 if (*szBuffer!=_T('\0'))
94 History(0,szBuffer);
95 else
96 break;
97 }
98 break;
99
100 case _T('A'):/*add an antry*/
101 History(0,param+2);
102 break;
103
104 case _T('S'):/*set history size*/
105 if ((tmp_int=_ttoi(param+2)))
106 set_size(tmp_int);
107 break;
108
109 default:
110 return 1;
111 }
112 }
113 else
114 {
115 for (h_tmp = Top->prev; h_tmp != Bottom; h_tmp = h_tmp->prev)
116 ConErrPuts(h_tmp->string);
117 }
118 return 0;
119 }
120
121 VOID set_size(INT new_size)
122 {
123 ASSERT(Top && Bottom);
124
125 while (new_size<size)
126 del(Top->prev);
127
128 max_size=new_size;
129 }
130
131
132 VOID InitHistory(VOID)
133 {
134 size = 0;
135
136 Top = cmd_alloc(sizeof(HIST_ENTRY));
137 if (!Top)
138 {
139 WARN("Cannot allocate memory for Top!\n");
140 return;
141 }
142 Bottom = cmd_alloc(sizeof(HIST_ENTRY));
143 if (!Bottom)
144 {
145 WARN("Cannot allocate memory for Bottom!\n");
146 cmd_free(Top);
147 Top = NULL;
148 return;
149 }
150
151 Top->prev = Bottom;
152 Top->next = NULL;
153 Top->string = NULL;
154
155 Bottom->prev = NULL;
156 Bottom->next = Top;
157 Bottom->string = NULL;
158
159 curr_ptr = Bottom;
160 }
161
162
163 VOID CleanHistory(VOID)
164 {
165 ASSERT(Top && Bottom);
166
167 while (Bottom->next != Top)
168 del(Bottom->next);
169
170 cmd_free(Top);
171 cmd_free(Bottom);
172 }
173
174
175 VOID History_del_current_entry(LPTSTR str)
176 {
177 LPHIST_ENTRY tmp;
178
179 ASSERT(Top && Bottom);
180
181 if (size == 0)
182 return;
183
184 if (curr_ptr == Bottom)
185 curr_ptr = Bottom->next;
186
187 if (curr_ptr == Top)
188 curr_ptr = Top->prev;
189
190
191 tmp = curr_ptr;
192 curr_ptr = curr_ptr->prev;
193 del(tmp);
194 History(-1, str);
195 }
196
197
198 static
199 VOID del(LPHIST_ENTRY item)
200 {
201 ASSERT(Top && Bottom);
202
203 if (item==NULL || item==Top || item==Bottom)
204 {
205 TRACE ("del in " __FILE__ ": returning\n"
206 "item is 0x%08x (Bottom is0x%08x)\n",
207 item, Bottom);
208 return;
209 }
210
211 /*free string's mem*/
212 if (item->string)
213 cmd_free(item->string);
214
215 /*set links in prev and next item*/
216 item->next->prev=item->prev;
217 item->prev->next=item->next;
218
219 cmd_free(item);
220
221 size--;
222 }
223
224 static
225 VOID add_at_bottom(LPTSTR string)
226 {
227 LPHIST_ENTRY tmp;
228
229 ASSERT(Top && Bottom);
230
231 /*delete first entry if maximum number of entries is reached*/
232 while (size>=max_size)
233 del(Top->prev);
234
235 while (_istspace(*string))
236 string++;
237
238 if (*string==_T('\0'))
239 return;
240
241 /*if new entry is the same than the last do not add it*/
242 if (size)
243 {
244 if (_tcscmp(string,Bottom->next->string)==0)
245 return;
246 }
247
248 /*create new empty Bottom*/
249 tmp = cmd_alloc(sizeof(HIST_ENTRY));
250 if (!tmp)
251 {
252 WARN("Cannot allocate memory for new Bottom!\n");
253 return;
254 }
255
256 /*fill old bottom with string, it will become new Bottom->next*/
257 Bottom->string = cmd_alloc((_tcslen(string)+1)*sizeof(TCHAR));
258 if (!Bottom->string)
259 {
260 WARN("Cannot allocate memory for Bottom->string!\n");
261 cmd_free(tmp);
262 return;
263 }
264 _tcscpy(Bottom->string,string);
265
266 tmp->next = Bottom;
267 tmp->prev = NULL;
268 tmp->string = NULL;
269
270 Bottom->prev = tmp;
271
272 /*save the new Bottom value*/
273 Bottom = tmp;
274
275 /*set new size*/
276 size++;
277 }
278
279
280 VOID History_move_to_bottom(VOID)
281 {
282 ASSERT(Top && Bottom);
283
284 curr_ptr = Bottom;
285 }
286
287 LPCTSTR PeekHistory(INT dir)
288 {
289 LPHIST_ENTRY entry = curr_ptr;
290
291 ASSERT(Top && Bottom);
292
293 if (dir == 0)
294 return NULL;
295
296 if (dir < 0)
297 {
298 /* key up */
299 if (entry->next == Top || entry == Top)
300 {
301 #ifdef WRAP_HISTORY
302 entry = Bottom;
303 #else
304 return NULL;
305 #endif
306 }
307 entry = entry->next;
308 }
309 else
310 {
311 /* key down */
312 if (entry->prev == Bottom || entry == Bottom)
313 {
314 #ifdef WRAP_HISTORY
315 entry = Top;
316 #else
317 return NULL;
318 #endif
319 }
320 entry = entry->prev;
321 }
322
323 return entry->string;
324 }
325
326 VOID History(INT dir, LPTSTR commandline)
327 {
328 ASSERT(Top && Bottom);
329
330 if (dir==0)
331 {
332 add_at_bottom(commandline);
333 curr_ptr = Bottom;
334 return;
335 }
336
337 if (size==0)
338 {
339 commandline[0]=_T('\0');
340 return;
341 }
342
343 if (dir<0)/*key up*/
344 {
345 if (curr_ptr->next==Top || curr_ptr==Top)
346 {
347 #ifdef WRAP_HISTORY
348 curr_ptr = Bottom;
349 #else
350 curr_ptr = Top;
351 commandline[0]=_T('\0');
352 return;
353 #endif
354 }
355
356 curr_ptr = curr_ptr->next;
357 if (curr_ptr->string)
358 _tcscpy(commandline,curr_ptr->string);
359 }
360
361 if (dir>0)
362 {
363 if (curr_ptr->prev==Bottom || curr_ptr==Bottom)
364 {
365 #ifdef WRAP_HISTORY
366 curr_ptr = Top;
367 #else
368 curr_ptr = Bottom;
369 commandline[0]=_T('\0');
370 return;
371 #endif
372 }
373
374 curr_ptr = curr_ptr->prev;
375 if (curr_ptr->string)
376 _tcscpy(commandline,curr_ptr->string);
377 }
378 }
379
380 #endif //#if FEATURE_HISTORY