xref: /petsc/src/sys/classes/viewer/impls/ascii/filev.c (revision 9fd2a872fac71d98bdeeea4f800da4f052f7a9fb)
1 
2 #include <../src/sys/classes/viewer/impls/ascii/asciiimpl.h> /*I "petscviewer.h" I*/
3 
4 #define QUEUESTRINGSIZE 8192
5 
6 static PetscErrorCode PetscViewerFileClose_ASCII(PetscViewer viewer)
7 {
8   PetscMPIInt        rank;
9   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
10   int                err;
11 
12   PetscFunctionBegin;
13   PetscCheck(!vascii->sviewer, PetscObjectComm((PetscObject)viewer), PETSC_ERR_ARG_WRONGSTATE, "Cannot call with outstanding call to PetscViewerRestoreSubViewer()");
14   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer), &rank));
15   if (rank == 0 && vascii->fd != stderr && vascii->fd != PETSC_STDOUT) {
16     if (vascii->fd && vascii->closefile) {
17       err = fclose(vascii->fd);
18       PetscCheck(!err, PETSC_COMM_SELF, PETSC_ERR_SYS, "fclose() failed on file");
19     }
20     if (vascii->storecompressed) {
21       char  par[PETSC_MAX_PATH_LEN], buf[PETSC_MAX_PATH_LEN];
22       FILE *fp;
23       PetscCall(PetscStrncpy(par, "gzip ", sizeof(par)));
24       PetscCall(PetscStrlcat(par, vascii->filename, sizeof(par)));
25 #if defined(PETSC_HAVE_POPEN)
26       PetscCall(PetscPOpen(PETSC_COMM_SELF, NULL, par, "r", &fp));
27       PetscCheck(!fgets(buf, 1024, fp), PETSC_COMM_SELF, PETSC_ERR_LIB, "Error from compression command %s\n%s", par, buf);
28       PetscCall(PetscPClose(PETSC_COMM_SELF, fp));
29 #else
30       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP_SYS, "Cannot run external programs on this machine");
31 #endif
32     }
33   }
34   PetscCall(PetscFree(vascii->filename));
35   PetscFunctionReturn(PETSC_SUCCESS);
36 }
37 
38 /* ----------------------------------------------------------------------*/
39 PetscErrorCode PetscViewerDestroy_ASCII(PetscViewer viewer)
40 {
41   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
42   PetscViewerLink   *vlink;
43   PetscBool          flg;
44 
45   PetscFunctionBegin;
46   PetscCheck(!vascii->sviewer, PetscObjectComm((PetscObject)viewer), PETSC_ERR_ARG_WRONGSTATE, "Cannot call with outstanding call to PetscViewerRestoreSubViewer()");
47   PetscCall(PetscViewerFileClose_ASCII(viewer));
48   PetscCall(PetscFree(vascii));
49 
50   /* remove the viewer from the list in the MPI Communicator */
51   if (Petsc_Viewer_keyval == MPI_KEYVAL_INVALID) PetscCallMPI(MPI_Comm_create_keyval(MPI_COMM_NULL_COPY_FN, Petsc_DelViewer, &Petsc_Viewer_keyval, (void *)0));
52 
53   PetscCallMPI(MPI_Comm_get_attr(PetscObjectComm((PetscObject)viewer), Petsc_Viewer_keyval, (void **)&vlink, (PetscMPIInt *)&flg));
54   if (flg) {
55     if (vlink && vlink->viewer == viewer) {
56       if (vlink->next) {
57         PetscCallMPI(MPI_Comm_set_attr(PetscObjectComm((PetscObject)viewer), Petsc_Viewer_keyval, vlink->next));
58       } else {
59         PetscCallMPI(MPI_Comm_delete_attr(PetscObjectComm((PetscObject)viewer), Petsc_Viewer_keyval));
60       }
61       PetscCall(PetscFree(vlink));
62     } else {
63       while (vlink && vlink->next) {
64         if (vlink->next->viewer == viewer) {
65           PetscViewerLink *nv = vlink->next;
66           vlink->next         = vlink->next->next;
67           PetscCall(PetscFree(nv));
68         }
69         vlink = vlink->next;
70       }
71     }
72   }
73 
74   if (Petsc_Viewer_Stdout_keyval != MPI_KEYVAL_INVALID) {
75     PetscViewer aviewer;
76     PetscCallMPI(MPI_Comm_get_attr(PetscObjectComm((PetscObject)viewer), Petsc_Viewer_Stdout_keyval, (void **)&aviewer, (PetscMPIInt *)&flg));
77     if (flg && aviewer == viewer) PetscCallMPI(MPI_Comm_delete_attr(PetscObjectComm((PetscObject)viewer), Petsc_Viewer_Stdout_keyval));
78   }
79   if (Petsc_Viewer_Stderr_keyval != MPI_KEYVAL_INVALID) {
80     PetscViewer aviewer;
81     PetscCallMPI(MPI_Comm_get_attr(PetscObjectComm((PetscObject)viewer), Petsc_Viewer_Stderr_keyval, (void **)&aviewer, (PetscMPIInt *)&flg));
82     if (flg && aviewer == viewer) PetscCallMPI(MPI_Comm_delete_attr(PetscObjectComm((PetscObject)viewer), Petsc_Viewer_Stderr_keyval));
83   }
84   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileSetName_C", NULL));
85   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileGetName_C", NULL));
86   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileGetMode_C", NULL));
87   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileSetMode_C", NULL));
88   PetscFunctionReturn(PETSC_SUCCESS);
89 }
90 
91 PetscErrorCode PetscViewerDestroy_ASCII_SubViewer(PetscViewer viewer)
92 {
93   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
94 
95   PetscFunctionBegin;
96   PetscCall(PetscViewerRestoreSubViewer(vascii->bviewer, 0, &viewer));
97   PetscFunctionReturn(PETSC_SUCCESS);
98 }
99 
100 PetscErrorCode PetscViewerFlush_ASCII(PetscViewer viewer)
101 {
102   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
103   MPI_Comm           comm;
104   PetscMPIInt        rank, size;
105   FILE              *fd = vascii->fd;
106 
107   PetscFunctionBegin;
108   PetscCheck(!vascii->sviewer, PetscObjectComm((PetscObject)viewer), PETSC_ERR_ARG_WRONGSTATE, "Cannot call with outstanding call to PetscViewerRestoreSubViewer()");
109   PetscCall(PetscObjectGetComm((PetscObject)viewer, &comm));
110   PetscCallMPI(MPI_Comm_rank(comm, &rank));
111   PetscCallMPI(MPI_Comm_size(comm, &size));
112 
113   if (!vascii->bviewer && rank == 0 && (vascii->mode != FILE_MODE_READ)) PetscCall(PetscFFlush(vascii->fd));
114 
115   if (vascii->allowsynchronized) {
116     PetscMPIInt tag, i, j, n = 0, dummy = 0;
117     char       *message;
118     MPI_Status  status;
119 
120     PetscCall(PetscCommDuplicate(comm, &comm, &tag));
121 
122     /* First processor waits for messages from all other processors */
123     if (rank == 0) {
124       /* flush my own messages that I may have queued up */
125       PrintfQueue next = vascii->petsc_printfqueuebase, previous;
126       for (i = 0; i < vascii->petsc_printfqueuelength; i++) {
127         if (!vascii->bviewer) {
128           PetscCall(PetscFPrintf(comm, fd, "%s", next->string));
129         } else {
130           PetscCall(PetscViewerASCIISynchronizedPrintf(vascii->bviewer, "%s", next->string));
131         }
132         previous = next;
133         next     = next->next;
134         PetscCall(PetscFree(previous->string));
135         PetscCall(PetscFree(previous));
136       }
137       vascii->petsc_printfqueue       = NULL;
138       vascii->petsc_printfqueuelength = 0;
139       for (i = 1; i < size; i++) {
140         /* to prevent a flood of messages to process zero, request each message separately */
141         PetscCallMPI(MPI_Send(&dummy, 1, MPI_INT, i, tag, comm));
142         PetscCallMPI(MPI_Recv(&n, 1, MPI_INT, i, tag, comm, &status));
143         for (j = 0; j < n; j++) {
144           PetscMPIInt size = 0;
145 
146           PetscCallMPI(MPI_Recv(&size, 1, MPI_INT, i, tag, comm, &status));
147           PetscCall(PetscMalloc1(size, &message));
148           PetscCallMPI(MPI_Recv(message, size, MPI_CHAR, i, tag, comm, &status));
149           if (!vascii->bviewer) {
150             PetscCall(PetscFPrintf(comm, fd, "%s", message));
151           } else {
152             PetscCall(PetscViewerASCIISynchronizedPrintf(vascii->bviewer, "%s", message));
153           }
154           PetscCall(PetscFree(message));
155         }
156       }
157     } else { /* other processors send queue to processor 0 */
158       PrintfQueue next = vascii->petsc_printfqueuebase, previous;
159 
160       PetscCallMPI(MPI_Recv(&dummy, 1, MPI_INT, 0, tag, comm, &status));
161       PetscCallMPI(MPI_Send(&vascii->petsc_printfqueuelength, 1, MPI_INT, 0, tag, comm));
162       for (i = 0; i < vascii->petsc_printfqueuelength; i++) {
163         PetscCallMPI(MPI_Send(&next->size, 1, MPI_INT, 0, tag, comm));
164         PetscCallMPI(MPI_Send(next->string, next->size, MPI_CHAR, 0, tag, comm));
165         previous = next;
166         next     = next->next;
167         PetscCall(PetscFree(previous->string));
168         PetscCall(PetscFree(previous));
169       }
170       vascii->petsc_printfqueue       = NULL;
171       vascii->petsc_printfqueuelength = 0;
172     }
173     PetscCall(PetscCommDestroy(&comm));
174   }
175   PetscFunctionReturn(PETSC_SUCCESS);
176 }
177 
178 /*@C
179     PetscViewerASCIIGetPointer - Extracts the file pointer from an ASCII `PetscViewer`.
180 
181     Not Collective, depending on the viewer the value may be meaningless except for process 0 of the viewer; No Fortran Support
182 
183     Input Parameter:
184 .    viewer - `PetscViewer` context, obtained from `PetscViewerASCIIOpen()`
185 
186     Output Parameter:
187 .    fd - file pointer
188 
189     Level: intermediate
190 
191     Note:
192     For the standard `PETSCVIEWERASCII` the value is valid only on process 0 of the viewer
193 
194 .seealso: [](sec_viewers), `PETSCVIEWERASCII`, `PetscViewerASCIIOpen()`, `PetscViewerDestroy()`, `PetscViewerSetType()`,
195           `PetscViewerCreate()`, `PetscViewerASCIIPrintf()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerFlush()`
196 @*/
197 PetscErrorCode PetscViewerASCIIGetPointer(PetscViewer viewer, FILE **fd)
198 {
199   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
200 
201   PetscFunctionBegin;
202   *fd = vascii->fd;
203   PetscFunctionReturn(PETSC_SUCCESS);
204 }
205 
206 PetscErrorCode PetscViewerFileGetMode_ASCII(PetscViewer viewer, PetscFileMode *mode)
207 {
208   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
209 
210   PetscFunctionBegin;
211   *mode = vascii->mode;
212   PetscFunctionReturn(PETSC_SUCCESS);
213 }
214 
215 PetscErrorCode PetscViewerFileSetMode_ASCII(PetscViewer viewer, PetscFileMode mode)
216 {
217   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
218 
219   PetscFunctionBegin;
220   vascii->mode = mode;
221   PetscFunctionReturn(PETSC_SUCCESS);
222 }
223 
224 /*
225    If petsc_history is on, then all Petsc*Printf() results are saved
226    if the appropriate (usually .petschistory) file.
227 */
228 PETSC_INTERN FILE *petsc_history;
229 
230 /*@
231     PetscViewerASCIISetTab - Causes `PetscViewer` to tab in a number of times before printing
232 
233     Not Collective, but only first processor in set has any effect; No Fortran Support
234 
235     Input Parameters:
236 +    viewer - obtained with `PetscViewerASCIIOpen()`
237 -    tabs - number of tabs
238 
239     Level: developer
240 
241     Note:
242      `PetscViewerASCIIPushTab()` and `PetscViewerASCIIPopTab()` are the preferred usage
243 
244 .seealso: [](sec_viewers), `PETSCVIEWERASCII`, `PetscPrintf()`, `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`,
245           `PetscViewerASCIIGetTab()`,
246           `PetscViewerASCIIPopTab()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerASCIIOpen()`,
247           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`, `PetscViewerASCIIGetPointer()`,
248           `PetscViewerASCIIPushTab()`
249 @*/
250 PetscErrorCode PetscViewerASCIISetTab(PetscViewer viewer, PetscInt tabs)
251 {
252   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
253   PetscBool          iascii;
254 
255   PetscFunctionBegin;
256   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
257   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
258   if (iascii) ascii->tab = tabs;
259   PetscFunctionReturn(PETSC_SUCCESS);
260 }
261 
262 /*@
263     PetscViewerASCIIGetTab - Return the number of tabs used by `PetscViewer`.
264 
265     Not Collective, meaningful on first processor only; No Fortran Support
266 
267     Input Parameters:
268 .    viewer - obtained with `PetscViewerASCIIOpen()`
269 
270     Output Parameters:
271 .    tabs - number of tabs
272 
273     Level: developer
274 
275 .seealso: [](sec_viewers), `PETSCVIEWERASCII`, `PetscPrintf()`, `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`,
276           `PetscViewerASCIISetTab()`,
277           `PetscViewerASCIIPopTab()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerASCIIOpen()`,
278           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`, `PetscViewerASCIIGetPointer()`, `PetscViewerASCIIPushTab()`
279 @*/
280 PetscErrorCode PetscViewerASCIIGetTab(PetscViewer viewer, PetscInt *tabs)
281 {
282   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
283   PetscBool          iascii;
284 
285   PetscFunctionBegin;
286   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
287   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
288   if (iascii && tabs) *tabs = ascii->tab;
289   PetscFunctionReturn(PETSC_SUCCESS);
290 }
291 
292 /*@
293     PetscViewerASCIIAddTab - Add to the number of times a `PETSCVIEWERASCII` viewer tabs before printing
294 
295     Not Collective, but only first processor in set has any effect; No Fortran Support
296 
297     Input Parameters:
298 +    viewer - obtained with `PetscViewerASCIIOpen()`
299 -    tabs - number of tabs
300 
301     Level: developer
302 
303     Note:
304      `PetscViewerASCIIPushTab()` and `PetscViewerASCIIPopTab()` are the preferred usage
305 
306 .seealso: [](sec_viewers), `PETSCVIEWERASCII`, `PetscPrintf()`, `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`,
307           `PetscViewerASCIIPopTab()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerASCIIOpen()`,
308           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`, `PetscViewerASCIIGetPointer()`, `PetscViewerASCIIPushTab()`
309 @*/
310 PetscErrorCode PetscViewerASCIIAddTab(PetscViewer viewer, PetscInt tabs)
311 {
312   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
313   PetscBool          iascii;
314 
315   PetscFunctionBegin;
316   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
317   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
318   if (iascii) ascii->tab += tabs;
319   PetscFunctionReturn(PETSC_SUCCESS);
320 }
321 
322 /*@
323     PetscViewerASCIISubtractTab - Subtracts from the number of times a `PETSCVIEWERASCII` viewer tabs before printing
324 
325     Not Collective, but only first processor in set has any effect; No Fortran Support
326 
327     Input Parameters:
328 +    viewer - obtained with `PetscViewerASCIIOpen()`
329 -    tabs - number of tabs
330 
331     Level: developer
332 
333     Note:
334      `PetscViewerASCIIPushTab()` and `PetscViewerASCIIPopTab()` are the preferred usage
335 
336 .seealso: [](sec_viewers), `PETSCVIEWERASCII`, `PetscPrintf()`, `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`,
337           `PetscViewerASCIIPopTab()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerASCIIOpen()`,
338           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`, `PetscViewerASCIIGetPointer()`,
339           `PetscViewerASCIIPushTab()`
340 @*/
341 PetscErrorCode PetscViewerASCIISubtractTab(PetscViewer viewer, PetscInt tabs)
342 {
343   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
344   PetscBool          iascii;
345 
346   PetscFunctionBegin;
347   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
348   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
349   if (iascii) ascii->tab -= tabs;
350   PetscFunctionReturn(PETSC_SUCCESS);
351 }
352 
353 /*@C
354     PetscViewerASCIIPushSynchronized - Allows calls to `PetscViewerASCIISynchronizedPrintf()` for this viewer
355 
356     Collective
357 
358     Input Parameters:
359 .    viewer - obtained with `PetscViewerASCIIOpen()`
360 
361     Level: intermediate
362 
363     Note:
364     See documentation of `PetscViewerASCIISynchronizedPrintf()` for more details how the synchronized output should be done properly.
365 
366 .seealso: [](sec_viewers), `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerFlush()`, `PetscViewerASCIIPopSynchronized()`,
367           `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`, `PetscViewerASCIIOpen()`,
368           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`
369 @*/
370 PetscErrorCode PetscViewerASCIIPushSynchronized(PetscViewer viewer)
371 {
372   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
373   PetscBool          iascii;
374 
375   PetscFunctionBegin;
376   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
377   PetscCheck(!ascii->sviewer, PetscObjectComm((PetscObject)viewer), PETSC_ERR_ARG_WRONGSTATE, "Cannot call with outstanding call to PetscViewerRestoreSubViewer()");
378   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
379   if (iascii) ascii->allowsynchronized++;
380   PetscFunctionReturn(PETSC_SUCCESS);
381 }
382 
383 /*@C
384     PetscViewerASCIIPopSynchronized - Undoes most recent `PetscViewerASCIIPushSynchronized()` for this viewer
385 
386     Collective
387 
388     Input Parameters:
389 .    viewer - obtained with `PetscViewerASCIIOpen()`
390 
391     Level: intermediate
392 
393     Note:
394     See documentation of `PetscViewerASCIISynchronizedPrintf()` for more details how the synchronized output should be done properly.
395 
396 .seealso: [](sec_viewers), `PetscViewerASCIIPushSynchronized()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerFlush()`,
397           `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`, `PetscViewerASCIIOpen()`,
398           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`
399 @*/
400 PetscErrorCode PetscViewerASCIIPopSynchronized(PetscViewer viewer)
401 {
402   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
403   PetscBool          iascii;
404 
405   PetscFunctionBegin;
406   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
407   PetscCheck(!ascii->sviewer, PetscObjectComm((PetscObject)viewer), PETSC_ERR_ARG_WRONGSTATE, "Cannot call with outstanding call to PetscViewerRestoreSubViewer()");
408   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
409   if (iascii) {
410     ascii->allowsynchronized--;
411     PetscCheck(ascii->allowsynchronized >= 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Called more times than PetscViewerASCIIPushSynchronized()");
412   }
413   PetscFunctionReturn(PETSC_SUCCESS);
414 }
415 
416 /*@C
417     PetscViewerASCIIPushTab - Adds one more tab to the amount that `PetscViewerASCIIPrintf()`
418      lines are tabbed.
419 
420     Not Collective, but only first processor in set has any effect; No Fortran Support
421 
422     Input Parameters:
423 .    viewer - obtained with `PetscViewerASCIIOpen()`
424 
425     Level: developer
426 
427 .seealso: [](sec_viewers), `PetscPrintf()`, `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`,
428           `PetscViewerASCIIPopTab()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerASCIIOpen()`,
429           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`, `PetscViewerASCIIGetPointer()`
430 @*/
431 PetscErrorCode PetscViewerASCIIPushTab(PetscViewer viewer)
432 {
433   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
434   PetscBool          iascii;
435 
436   PetscFunctionBegin;
437   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
438   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
439   if (iascii) ascii->tab++;
440   PetscFunctionReturn(PETSC_SUCCESS);
441 }
442 
443 /*@C
444     PetscViewerASCIIPopTab - Removes one tab from the amount that `PetscViewerASCIIPrintf()` lines are tabbed that was provided by
445     `PetscViewerASCIIPushTab()`
446 
447     Not Collective, but only first processor in set has any effect; No Fortran Support
448 
449     Input Parameters:
450 .    viewer - obtained with `PetscViewerASCIIOpen()`
451 
452     Level: developer
453 
454 .seealso: [](sec_viewers), `PetscPrintf()`, `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`,
455           `PetscViewerASCIIPushTab()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerASCIIOpen()`,
456           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`, `PetscViewerASCIIGetPointer()`
457 @*/
458 PetscErrorCode PetscViewerASCIIPopTab(PetscViewer viewer)
459 {
460   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
461   PetscBool          iascii;
462 
463   PetscFunctionBegin;
464   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
465   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
466   if (iascii) {
467     PetscCheck(ascii->tab > 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "More tabs popped than pushed");
468     ascii->tab--;
469   }
470   PetscFunctionReturn(PETSC_SUCCESS);
471 }
472 
473 /*@
474     PetscViewerASCIIUseTabs - Turns on or off the use of tabs with the ASCII `PetscViewer`
475 
476     Not Collective, but only first processor in set has any effect; No Fortran Support
477 
478     Input Parameters:
479 +    viewer - obtained with `PetscViewerASCIIOpen()`
480 -    flg - `PETSC_TRUE` or `PETSC_FALSE`
481 
482     Level: developer
483 
484 .seealso: [](sec_viewers), `PetscPrintf()`, `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`,
485           `PetscViewerASCIIPopTab()`, `PetscViewerASCIISynchronizedPrintf()`, `PetscViewerASCIIPushTab()`, `PetscViewerASCIIOpen()`,
486           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`, `PetscViewerASCIIGetPointer()`
487 @*/
488 PetscErrorCode PetscViewerASCIIUseTabs(PetscViewer viewer, PetscBool flg)
489 {
490   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
491   PetscBool          iascii;
492 
493   PetscFunctionBegin;
494   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
495   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
496   if (iascii) {
497     if (flg) ascii->tab = ascii->tab_store;
498     else {
499       ascii->tab_store = ascii->tab;
500       ascii->tab       = 0;
501     }
502   }
503   PetscFunctionReturn(PETSC_SUCCESS);
504 }
505 
506 /* ----------------------------------------------------------------------- */
507 
508 /*@C
509     PetscViewerASCIIPrintf - Prints to a file, only from the first
510     processor in the `PetscViewer` of type `PETSCVIEWERASCII`
511 
512     Not Collective, but only first processor in set has any effect
513 
514     Input Parameters:
515 +    viewer - obtained with `PetscViewerASCIIOpen()`
516 -    format - the usual printf() format string
517 
518     Level: developer
519 
520     Fortran Note:
521     The call sequence is `PetscViewerASCIIPrintf`(PetscViewer, character(*), int ierr) from Fortran.
522     That is, you can only pass a single character string from Fortran.
523 
524 .seealso: [](sec_viewers), `PetscPrintf()`, `PetscSynchronizedPrintf()`, `PetscViewerASCIIOpen()`,
525           `PetscViewerASCIIPushTab()`, `PetscViewerASCIIPopTab()`, `PetscViewerASCIISynchronizedPrintf()`,
526           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`, `PetscViewerASCIIGetPointer()`, `PetscViewerASCIIPushSynchronized()`
527 @*/
528 PetscErrorCode PetscViewerASCIIPrintf(PetscViewer viewer, const char format[], ...)
529 {
530   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
531   PetscMPIInt        rank;
532   PetscInt           tab, intab = ascii->tab;
533   FILE              *fd = ascii->fd;
534   PetscBool          iascii;
535 
536   PetscFunctionBegin;
537   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
538   PetscCheck(!ascii->sviewer, PetscObjectComm((PetscObject)viewer), PETSC_ERR_ARG_WRONGSTATE, "Cannot call with outstanding call to PetscViewerRestoreSubViewer()");
539   PetscValidCharPointer(format, 2);
540   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
541   PetscCheck(iascii, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Not ASCII PetscViewer");
542   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer), &rank));
543   if (rank) PetscFunctionReturn(PETSC_SUCCESS);
544 
545   if (ascii->bviewer) { /* pass string up to parent viewer */
546     char   *string;
547     va_list Argp;
548     size_t  fullLength;
549 
550     PetscCall(PetscCalloc1(QUEUESTRINGSIZE, &string));
551     va_start(Argp, format);
552     PetscCall(PetscVSNPrintf(string, QUEUESTRINGSIZE, format, &fullLength, Argp));
553     va_end(Argp);
554     PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "%s", string));
555     PetscCall(PetscFree(string));
556   } else { /* write directly to file */
557     va_list Argp;
558     /* flush my own messages that I may have queued up */
559     PrintfQueue next = ascii->petsc_printfqueuebase, previous;
560     PetscInt    i;
561     for (i = 0; i < ascii->petsc_printfqueuelength; i++) {
562       PetscCall(PetscFPrintf(PETSC_COMM_SELF, fd, "%s", next->string));
563       previous = next;
564       next     = next->next;
565       PetscCall(PetscFree(previous->string));
566       PetscCall(PetscFree(previous));
567     }
568     ascii->petsc_printfqueue       = NULL;
569     ascii->petsc_printfqueuelength = 0;
570     tab                            = intab;
571     while (tab--) PetscCall(PetscFPrintf(PETSC_COMM_SELF, fd, "  "));
572 
573     va_start(Argp, format);
574     PetscCall((*PetscVFPrintf)(fd, format, Argp));
575     PetscCall(PetscFFlush(fd));
576     if (petsc_history) {
577       va_start(Argp, format);
578       tab = intab;
579       while (tab--) PetscCall(PetscFPrintf(PETSC_COMM_SELF, petsc_history, "  "));
580       PetscCall((*PetscVFPrintf)(petsc_history, format, Argp));
581       PetscCall(PetscFFlush(petsc_history));
582     }
583     va_end(Argp);
584   }
585   PetscFunctionReturn(PETSC_SUCCESS);
586 }
587 
588 /*@C
589      PetscViewerFileSetName - Sets the name of the file the `PetscViewer` uses.
590 
591     Collective
592 
593   Input Parameters:
594 +  viewer - the `PetscViewer`; for example, of type `PETSCVIEWERASCII` or `PETSCVIEWERBINARY`
595 -  name - the name of the file it should use
596 
597     Level: advanced
598 
599 .seealso: [](sec_viewers), `PetscViewerCreate()`, `PetscViewerSetType()`, `PetscViewerASCIIOpen()`, `PetscViewerBinaryOpen()`, `PetscViewerDestroy()`,
600           `PetscViewerASCIIGetPointer()`, `PetscViewerASCIIPrintf()`, `PetscViewerASCIISynchronizedPrintf()`
601 @*/
602 PetscErrorCode PetscViewerFileSetName(PetscViewer viewer, const char name[])
603 {
604   char filename[PETSC_MAX_PATH_LEN];
605 
606   PetscFunctionBegin;
607   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
608   PetscValidCharPointer(name, 2);
609   PetscCall(PetscStrreplace(PetscObjectComm((PetscObject)viewer), name, filename, sizeof(filename)));
610   PetscTryMethod(viewer, "PetscViewerFileSetName_C", (PetscViewer, const char[]), (viewer, filename));
611   PetscFunctionReturn(PETSC_SUCCESS);
612 }
613 
614 /*@C
615      PetscViewerFileGetName - Gets the name of the file the `PetscViewer` uses.
616 
617     Not Collective
618 
619   Input Parameter:
620 .  viewer - the `PetscViewer`
621 
622   Output Parameter:
623 .  name - the name of the file it is using
624 
625     Level: advanced
626 
627 .seealso: [](sec_viewers), `PetscViewerCreate()`, `PetscViewerSetType()`, `PetscViewerASCIIOpen()`, `PetscViewerBinaryOpen()`, `PetscViewerFileSetName()`
628 @*/
629 PetscErrorCode PetscViewerFileGetName(PetscViewer viewer, const char **name)
630 {
631   PetscFunctionBegin;
632   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
633   PetscValidPointer(name, 2);
634   PetscUseMethod(viewer, "PetscViewerFileGetName_C", (PetscViewer, const char **), (viewer, name));
635   PetscFunctionReturn(PETSC_SUCCESS);
636 }
637 
638 PetscErrorCode PetscViewerFileGetName_ASCII(PetscViewer viewer, const char **name)
639 {
640   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
641 
642   PetscFunctionBegin;
643   *name = vascii->filename;
644   PetscFunctionReturn(PETSC_SUCCESS);
645 }
646 
647 PetscErrorCode PetscViewerFileSetName_ASCII(PetscViewer viewer, const char name[])
648 {
649   size_t             len;
650   char               fname[PETSC_MAX_PATH_LEN], *gz = NULL;
651   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
652   PetscBool          isstderr, isstdout;
653   PetscMPIInt        rank;
654 
655   PetscFunctionBegin;
656   PetscCall(PetscViewerFileClose_ASCII(viewer));
657   if (!name) PetscFunctionReturn(PETSC_SUCCESS);
658   PetscCall(PetscStrallocpy(name, &vascii->filename));
659 
660   /* Is this file to be compressed */
661   vascii->storecompressed = PETSC_FALSE;
662 
663   PetscCall(PetscStrstr(vascii->filename, ".gz", &gz));
664   if (gz) {
665     PetscCall(PetscStrlen(gz, &len));
666     if (len == 3) {
667       PetscCheck(vascii->mode == FILE_MODE_WRITE, PetscObjectComm((PetscObject)viewer), PETSC_ERR_SUP, "Cannot open ASCII PetscViewer file that is compressed; uncompress it manually first");
668       *gz                     = 0;
669       vascii->storecompressed = PETSC_TRUE;
670     }
671   }
672   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer), &rank));
673   if (rank == 0) {
674     PetscCall(PetscStrcmp(name, "stderr", &isstderr));
675     PetscCall(PetscStrcmp(name, "stdout", &isstdout));
676     /* empty filename means stdout */
677     if (name[0] == 0) isstdout = PETSC_TRUE;
678     if (isstderr) vascii->fd = PETSC_STDERR;
679     else if (isstdout) vascii->fd = PETSC_STDOUT;
680     else {
681       PetscCall(PetscFixFilename(name, fname));
682       switch (vascii->mode) {
683       case FILE_MODE_READ:
684         vascii->fd = fopen(fname, "r");
685         break;
686       case FILE_MODE_WRITE:
687         vascii->fd = fopen(fname, "w");
688         break;
689       case FILE_MODE_APPEND:
690         vascii->fd = fopen(fname, "a");
691         break;
692       case FILE_MODE_UPDATE:
693         vascii->fd = fopen(fname, "r+");
694         if (!vascii->fd) vascii->fd = fopen(fname, "w+");
695         break;
696       case FILE_MODE_APPEND_UPDATE:
697         /* I really want a file which is opened at the end for updating,
698            not a+, which opens at the beginning, but makes writes at the end.
699         */
700         vascii->fd = fopen(fname, "r+");
701         if (!vascii->fd) vascii->fd = fopen(fname, "w+");
702         else {
703           int ret = fseek(vascii->fd, 0, SEEK_END);
704           PetscCheck(!ret, PETSC_COMM_SELF, PETSC_ERR_LIB, "fseek() failed with error code %d", ret);
705         }
706         break;
707       default:
708         SETERRQ(PetscObjectComm((PetscObject)viewer), PETSC_ERR_SUP, "Unsupported file mode %s", PetscFileModes[vascii->mode]);
709       }
710       PetscCheck(vascii->fd, PETSC_COMM_SELF, PETSC_ERR_FILE_OPEN, "Cannot open PetscViewer file: %s", fname);
711     }
712   }
713 #if defined(PETSC_USE_LOG)
714   PetscCall(PetscLogObjectState((PetscObject)viewer, "File: %s", name));
715 #endif
716   PetscFunctionReturn(PETSC_SUCCESS);
717 }
718 
719 PetscErrorCode PetscViewerGetSubViewer_ASCII(PetscViewer viewer, MPI_Comm subcomm, PetscViewer *outviewer)
720 {
721   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data, *ovascii;
722 
723   PetscFunctionBegin;
724   PetscCall(PetscViewerASCIIPushSynchronized(viewer));
725   PetscCheck(!vascii->sviewer, PETSC_COMM_SELF, PETSC_ERR_ORDER, "SubViewer already obtained from PetscViewer and not restored");
726   /*
727      The following line is a bug; it does another PetscViewerASCIIPushSynchronized() on viewer, but if it is removed the code won't work
728      because it relies on this behavior in other places. In particular this line causes the synchronized flush to occur when the viewer is destroyed
729      (since the count never gets to zero) in some examples this displays information that otherwise would be lost
730 
731      This code also means another call to PetscViewerASCIIPopSynchronized() must be made after the PetscViewerRestoreSubViewer(), see, for example,
732      PCView_GASM().
733   */
734   PetscCall(PetscViewerASCIIPushSynchronized(viewer));
735   PetscCall(PetscViewerCreate(subcomm, outviewer));
736   PetscCall(PetscViewerSetType(*outviewer, PETSCVIEWERASCII));
737   PetscCall(PetscViewerASCIIPushSynchronized(*outviewer));
738   ovascii            = (PetscViewer_ASCII *)(*outviewer)->data;
739   ovascii->fd        = vascii->fd;
740   ovascii->tab       = vascii->tab;
741   ovascii->closefile = PETSC_FALSE;
742 
743   vascii->sviewer                                      = *outviewer;
744   (*outviewer)->format                                 = viewer->format;
745   ((PetscViewer_ASCII *)((*outviewer)->data))->bviewer = viewer;
746   (*outviewer)->ops->destroy                           = PetscViewerDestroy_ASCII_SubViewer;
747   PetscFunctionReturn(PETSC_SUCCESS);
748 }
749 
750 PetscErrorCode PetscViewerRestoreSubViewer_ASCII(PetscViewer viewer, MPI_Comm comm, PetscViewer *outviewer)
751 {
752   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)viewer->data;
753 
754   PetscFunctionBegin;
755   PetscCheck(ascii->sviewer, PETSC_COMM_SELF, PETSC_ERR_ORDER, "SubViewer never obtained from PetscViewer");
756   PetscCheck(ascii->sviewer == *outviewer, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "This PetscViewer did not generate this SubViewer");
757 
758   PetscCall(PetscViewerASCIIPopSynchronized(*outviewer));
759   ascii->sviewer             = NULL;
760   (*outviewer)->ops->destroy = PetscViewerDestroy_ASCII;
761   PetscCall(PetscViewerDestroy(outviewer));
762   PetscCall(PetscViewerASCIIPopSynchronized(viewer));
763   PetscFunctionReturn(PETSC_SUCCESS);
764 }
765 
766 PetscErrorCode PetscViewerView_ASCII(PetscViewer v, PetscViewer viewer)
767 {
768   PetscViewer_ASCII *ascii = (PetscViewer_ASCII *)v->data;
769 
770   PetscFunctionBegin;
771   if (ascii->filename) PetscCall(PetscViewerASCIIPrintf(viewer, "Filename: %s\n", ascii->filename));
772   PetscFunctionReturn(PETSC_SUCCESS);
773 }
774 
775 /*MC
776    PETSCVIEWERASCII - A viewer that prints to stdout or an ASCII file
777 
778   Level: beginner
779 
780 .seealso: [](sec_viewers), `PETSC_VIEWER_STDOUT_()`, `PETSC_VIEWER_STDOUT_SELF`, `PETSC_VIEWER_STDOUT_WORLD`, `PetscViewerCreate()`, `PetscViewerASCIIOpen()`,
781           `PetscViewerMatlabOpen()`, `VecView()`, `DMView()`, `PetscViewerMatlabPutArray()`, `PETSCVIEWERBINARY`, `PETSCVIEWERMATLAB`,
782           `PetscViewerFileSetName()`, `PetscViewerFileSetMode()`, `PetscViewerFormat`, `PetscViewerType`, `PetscViewerSetType()`
783 M*/
784 PETSC_EXTERN PetscErrorCode PetscViewerCreate_ASCII(PetscViewer viewer)
785 {
786   PetscViewer_ASCII *vascii;
787 
788   PetscFunctionBegin;
789   PetscCall(PetscNew(&vascii));
790   viewer->data = (void *)vascii;
791 
792   viewer->ops->destroy          = PetscViewerDestroy_ASCII;
793   viewer->ops->flush            = PetscViewerFlush_ASCII;
794   viewer->ops->getsubviewer     = PetscViewerGetSubViewer_ASCII;
795   viewer->ops->restoresubviewer = PetscViewerRestoreSubViewer_ASCII;
796   viewer->ops->view             = PetscViewerView_ASCII;
797   viewer->ops->read             = PetscViewerASCIIRead;
798 
799   /* defaults to stdout unless set with PetscViewerFileSetName() */
800   vascii->fd        = PETSC_STDOUT;
801   vascii->mode      = FILE_MODE_WRITE;
802   vascii->bviewer   = NULL;
803   vascii->subviewer = NULL;
804   vascii->sviewer   = NULL;
805   vascii->tab       = 0;
806   vascii->tab_store = 0;
807   vascii->filename  = NULL;
808   vascii->closefile = PETSC_TRUE;
809 
810   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileSetName_C", PetscViewerFileSetName_ASCII));
811   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileGetName_C", PetscViewerFileGetName_ASCII));
812   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileGetMode_C", PetscViewerFileGetMode_ASCII));
813   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileSetMode_C", PetscViewerFileSetMode_ASCII));
814   PetscFunctionReturn(PETSC_SUCCESS);
815 }
816 
817 /*@C
818     PetscViewerASCIISynchronizedPrintf - Prints synchronized output to the specified file from
819     several processors.  Output of the first processor is followed by that of the
820     second, etc.
821 
822     Not Collective, must call collective `PetscViewerFlush()` to get the results out
823 
824     Input Parameters:
825 +   viewer - the `PETSCVIEWERASCII` `PetscViewer`
826 -   format - the usual printf() format string
827 
828     Level: intermediate
829 
830     Notes:
831     You must have previously called `PetscViewerASCIIPushSynchronized()` to allow this routine to be called.
832     Then you can do multiple independent calls to this routine.
833 
834     The actual synchronized print is then done using `PetscViewerFlush()`.
835     `PetscViewerASCIIPopSynchronized()` should be then called if we are already done with the synchronized output
836     to conclude the "synchronized session".
837 
838     So the typical calling sequence looks like
839 .vb
840     PetscViewerASCIIPushSynchronized(viewer);
841     PetscViewerASCIISynchronizedPrintf(viewer, ...);
842     PetscViewerASCIISynchronizedPrintf(viewer, ...);
843     ...
844     PetscViewerFlush(viewer);
845     PetscViewerASCIISynchronizedPrintf(viewer, ...);
846     PetscViewerASCIISynchronizedPrintf(viewer, ...);
847     ...
848     PetscViewerFlush(viewer);
849    PetscViewerASCIIPopSynchronized(viewer);
850 .ve
851 
852     Fortran Note:
853       Can only print a single character* string
854 
855 .seealso: [](sec_viewers), `PetscViewerASCIIPushSynchronized()`, `PetscViewerFlush()`, `PetscViewerASCIIPopSynchronized()`,
856           `PetscSynchronizedPrintf()`, `PetscViewerASCIIPrintf()`, `PetscViewerASCIIOpen()`,
857           `PetscViewerCreate()`, `PetscViewerDestroy()`, `PetscViewerSetType()`
858 @*/
859 PetscErrorCode PetscViewerASCIISynchronizedPrintf(PetscViewer viewer, const char format[], ...)
860 {
861   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
862   PetscMPIInt        rank;
863   PetscInt           tab = vascii->tab;
864   MPI_Comm           comm;
865   FILE              *fp;
866   PetscBool          iascii, hasbviewer = PETSC_FALSE;
867 
868   PetscFunctionBegin;
869   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
870   PetscValidCharPointer(format, 2);
871   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
872   PetscCheck(iascii, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Not ASCII PetscViewer");
873   PetscCheck(vascii->allowsynchronized, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "First call PetscViewerASCIIPushSynchronized() to allow this call");
874 
875   PetscCall(PetscObjectGetComm((PetscObject)viewer, &comm));
876   PetscCallMPI(MPI_Comm_rank(comm, &rank));
877 
878   if (vascii->bviewer) {
879     hasbviewer = PETSC_TRUE;
880     if (rank == 0) {
881       vascii = (PetscViewer_ASCII *)vascii->bviewer->data;
882       PetscCall(PetscObjectGetComm((PetscObject)viewer, &comm));
883       PetscCallMPI(MPI_Comm_rank(comm, &rank));
884     }
885   }
886 
887   fp = vascii->fd;
888 
889   if (rank == 0 && !hasbviewer) { /* First processor prints immediately to fp */
890     va_list Argp;
891     /* flush my own messages that I may have queued up */
892     PrintfQueue next = vascii->petsc_printfqueuebase, previous;
893     PetscInt    i;
894     for (i = 0; i < vascii->petsc_printfqueuelength; i++) {
895       PetscCall(PetscFPrintf(comm, fp, "%s", next->string));
896       previous = next;
897       next     = next->next;
898       PetscCall(PetscFree(previous->string));
899       PetscCall(PetscFree(previous));
900     }
901     vascii->petsc_printfqueue       = NULL;
902     vascii->petsc_printfqueuelength = 0;
903 
904     while (tab--) PetscCall(PetscFPrintf(PETSC_COMM_SELF, fp, "  "));
905 
906     va_start(Argp, format);
907     PetscCall((*PetscVFPrintf)(fp, format, Argp));
908     PetscCall(PetscFFlush(fp));
909     if (petsc_history) {
910       va_start(Argp, format);
911       PetscCall((*PetscVFPrintf)(petsc_history, format, Argp));
912       PetscCall(PetscFFlush(petsc_history));
913     }
914     va_end(Argp);
915   } else { /* other processors add to queue */
916     char       *string;
917     va_list     Argp;
918     size_t      fullLength;
919     PrintfQueue next;
920 
921     PetscCall(PetscNew(&next));
922     if (vascii->petsc_printfqueue) {
923       vascii->petsc_printfqueue->next = next;
924       vascii->petsc_printfqueue       = next;
925     } else {
926       vascii->petsc_printfqueuebase = vascii->petsc_printfqueue = next;
927     }
928     vascii->petsc_printfqueuelength++;
929     next->size = QUEUESTRINGSIZE;
930     PetscCall(PetscCalloc1(next->size, &next->string));
931     string = next->string;
932     tab *= 2;
933     while (tab--) *string++ = ' ';
934     va_start(Argp, format);
935     PetscCall(PetscVSNPrintf(string, next->size - 2 * vascii->tab, format, &fullLength, Argp));
936     va_end(Argp);
937     if (fullLength > (size_t)(next->size - 2 * vascii->tab)) {
938       PetscCall(PetscFree(next->string));
939       next->size = fullLength + 2 * vascii->tab;
940       PetscCall(PetscCalloc1(next->size, &next->string));
941       string = next->string;
942       tab    = 2 * vascii->tab;
943       while (tab--) *string++ = ' ';
944       va_start(Argp, format);
945       PetscCall(PetscVSNPrintf(string, next->size - 2 * vascii->tab, format, NULL, Argp));
946       va_end(Argp);
947     }
948   }
949   PetscFunctionReturn(PETSC_SUCCESS);
950 }
951 
952 /*@C
953    PetscViewerASCIIRead - Reads from a ASCII file
954 
955    Only process 0 in the `PetscViewer` may call this
956 
957    Input Parameters:
958 +  viewer - the `PETSCVIEWERASCII` viewer
959 .  data - location to write the data
960 .  num - number of items of data to read
961 -  datatype - type of data to read
962 
963    Output Parameters:
964 .  count - number of items of data actually read, or `NULL`
965 
966    Level: beginner
967 
968 .seealso: [](sec_viewers), `PetscViewerASCIIOpen()`, `PetscViewerPushFormat()`, `PetscViewerDestroy()`, `PetscViewerCreate()`, `PetscViewerFileSetMode()`, `PetscViewerFileSetName()`
969           `VecView()`, `MatView()`, `VecLoad()`, `MatLoad()`, `PetscViewerBinaryGetDescriptor()`,
970           `PetscViewerBinaryGetInfoPointer()`, `PetscFileMode`, `PetscViewer`, `PetscViewerBinaryRead()`
971 @*/
972 PetscErrorCode PetscViewerASCIIRead(PetscViewer viewer, void *data, PetscInt num, PetscInt *count, PetscDataType dtype)
973 {
974   PetscViewer_ASCII *vascii = (PetscViewer_ASCII *)viewer->data;
975   FILE              *fd     = vascii->fd;
976   PetscInt           i;
977   int                ret = 0;
978   PetscMPIInt        rank;
979 
980   PetscFunctionBegin;
981   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
982   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer), &rank));
983   PetscCheck(rank == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Can only be called from process 0 in the PetscViewer");
984   for (i = 0; i < num; i++) {
985     if (dtype == PETSC_CHAR) ret = fscanf(fd, "%c", &(((char *)data)[i]));
986     else if (dtype == PETSC_STRING) ret = fscanf(fd, "%s", &(((char *)data)[i]));
987     else if (dtype == PETSC_INT) ret = fscanf(fd, "%" PetscInt_FMT, &(((PetscInt *)data)[i]));
988     else if (dtype == PETSC_ENUM) ret = fscanf(fd, "%d", &(((int *)data)[i]));
989     else if (dtype == PETSC_INT64) ret = fscanf(fd, "%" PetscInt64_FMT, &(((PetscInt64 *)data)[i]));
990     else if (dtype == PETSC_LONG) ret = fscanf(fd, "%ld", &(((long *)data)[i]));
991     else if (dtype == PETSC_FLOAT) ret = fscanf(fd, "%f", &(((float *)data)[i]));
992     else if (dtype == PETSC_DOUBLE) ret = fscanf(fd, "%lg", &(((double *)data)[i]));
993 #if defined(PETSC_USE_REAL___FLOAT128)
994     else if (dtype == PETSC___FLOAT128) {
995       double tmp;
996       ret                     = fscanf(fd, "%lg", &tmp);
997       ((__float128 *)data)[i] = tmp;
998     }
999 #endif
1000     else
1001       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Data type %d not supported", (int)dtype);
1002     PetscCheck(ret, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Conversion error for data type %d", (int)dtype);
1003     if (ret < 0) break; /* Proxy for EOF, need to check for it in configure */
1004   }
1005   if (count) *count = i;
1006   else PetscCheck(ret >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Insufficient data, read only %" PetscInt_FMT " < %" PetscInt_FMT " items", i, num);
1007   PetscFunctionReturn(PETSC_SUCCESS);
1008 }
1009