1: #include <petsc/private/viewerimpl.h>

  3: typedef struct {
  4:   char     *string; /* string where info is stored */
  5:   char     *head;   /* pointer to beginning of unused portion */
  6:   size_t    curlen, maxlen;
  7:   PetscBool ownstring; /* string viewer is responsible for freeing the string */
  8: } PetscViewer_String;

 10: static PetscErrorCode PetscViewerDestroy_String(PetscViewer viewer)
 11: {
 12:   PetscViewer_String *vstr = (PetscViewer_String *)viewer->data;

 14:   PetscFunctionBegin;
 15:   if (vstr->ownstring) PetscCall(PetscFree(vstr->string));
 16:   PetscCall(PetscFree(vstr));
 17:   PetscFunctionReturn(PETSC_SUCCESS);
 18: }

 20: /*@C
 21:   PetscViewerStringSPrintf - Prints information to a `PETSCVIEWERSTRING` `PetscViewer` object

 23:   Logically Collective; No Fortran Support

 25:   Input Parameters:
 26: + viewer - a string `PetscViewer`, formed by `PetscViewerStringOpen()`
 27: - format - the format of the input

 29:   Level: developer

 31:   Note:
 32:   Though this is collective each MPI process maintains a separate string

 34: .seealso: [](sec_viewers), `PETSCVIEWERSTRING`, `PetscViewerStringOpen()`, `PetscViewerStringGetStringRead()`, `PetscViewerStringSetString()`
 35: @*/
 36: PetscErrorCode PetscViewerStringSPrintf(PetscViewer viewer, const char format[], ...)
 37: {
 38:   va_list             Argp;
 39:   size_t              fullLength;
 40:   size_t              shift, cshift;
 41:   PetscBool           isstring;
 42:   char                tmp[4096];
 43:   PetscViewer_String *vstr = (PetscViewer_String *)viewer->data;

 45:   PetscFunctionBegin;
 47:   PetscAssertPointer(format, 2);
 48:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSTRING, &isstring));
 49:   if (!isstring) PetscFunctionReturn(PETSC_SUCCESS);
 50:   PetscCheck(vstr->string, PETSC_COMM_SELF, PETSC_ERR_ORDER, "Must call PetscViewerStringSetString() before using");

 52:   va_start(Argp, format);
 53:   PetscCall(PetscVSNPrintf(tmp, sizeof(tmp), format, &fullLength, Argp));
 54:   va_end(Argp);
 55:   PetscCall(PetscStrlen(tmp, &shift));
 56:   cshift = shift + 1;
 57:   if (cshift >= vstr->maxlen - vstr->curlen - 1) cshift = vstr->maxlen - vstr->curlen - 1;
 58:   PetscCall(PetscMemcpy(vstr->head, tmp, cshift));
 59:   vstr->head[cshift - 1] = '\0';
 60:   vstr->head += shift;
 61:   vstr->curlen += shift;
 62:   PetscFunctionReturn(PETSC_SUCCESS);
 63: }

 65: /*@C
 66:   PetscViewerStringOpen - Opens a string as a `PETSCVIEWERSTRING` `PetscViewer`. This is a very
 67:   simple `PetscViewer`; information on the object is simply stored into
 68:   the string in a fairly nice way.

 70:   Collective; No Fortran Support

 72:   Input Parameters:
 73: + comm   - the communicator
 74: . string - the string to use
 75: - len    - the string length

 77:   Output Parameter:
 78: . lab - the `PetscViewer`

 80:   Level: advanced

 82: .seealso: [](sec_viewers), `PETSCVIEWERSTRING`, `PetscViewerDestroy()`, `PetscViewerStringSPrintf()`, `PetscViewerStringGetStringRead()`, `PetscViewerStringSetString()`
 83: @*/
 84: PetscErrorCode PetscViewerStringOpen(MPI_Comm comm, char string[], size_t len, PetscViewer *lab)
 85: {
 86:   PetscFunctionBegin;
 87:   PetscCall(PetscViewerCreate(comm, lab));
 88:   PetscCall(PetscViewerSetType(*lab, PETSCVIEWERSTRING));
 89:   PetscCall(PetscViewerStringSetString(*lab, string, len));
 90:   PetscFunctionReturn(PETSC_SUCCESS);
 91: }

 93: static PetscErrorCode PetscViewerGetSubViewer_String(PetscViewer viewer, MPI_Comm comm, PetscViewer *sviewer)
 94: {
 95:   PetscViewer_String *vstr = (PetscViewer_String *)viewer->data;

 97:   PetscFunctionBegin;
 98:   PetscCall(PetscViewerStringOpen(PETSC_COMM_SELF, vstr->head, vstr->maxlen - vstr->curlen, sviewer));
 99:   PetscFunctionReturn(PETSC_SUCCESS);
100: }

102: static PetscErrorCode PetscViewerRestoreSubViewer_String(PetscViewer viewer, MPI_Comm comm, PetscViewer *sviewer)
103: {
104:   PetscViewer_String *iviewer = (PetscViewer_String *)(*sviewer)->data;
105:   PetscViewer_String *vstr    = (PetscViewer_String *)viewer->data;

107:   PetscFunctionBegin;
108:   vstr->head = iviewer->head;
109:   vstr->curlen += iviewer->curlen;
110:   PetscCall(PetscViewerDestroy(sviewer));
111:   PetscFunctionReturn(PETSC_SUCCESS);
112: }

114: /*MC
115:    PETSCVIEWERSTRING - A viewer that writes to a string

117:   Level: beginner

119: .seealso: [](sec_viewers), `PetscViewerStringOpen()`, `PetscViewerStringSPrintf()`, `PetscViewerSocketOpen()`, `PetscViewerDrawOpen()`, `PETSCVIEWERSOCKET`,
120:           `PetscViewerCreate()`, `PetscViewerASCIIOpen()`, `PetscViewerBinaryOpen()`, `PETSCVIEWERBINARY`, `PETSCVIEWERDRAW`,
121:           `PetscViewerMatlabOpen()`, `VecView()`, `DMView()`, `PetscViewerMatlabPutArray()`, `PETSCVIEWERASCII`, `PETSCVIEWERMATLAB`,
122:           `PetscViewerFileSetName()`, `PetscViewerFileSetMode()`, `PetscViewerFormat`, `PetscViewerType`, `PetscViewerSetType()`
123: M*/

125: PETSC_EXTERN PetscErrorCode PetscViewerCreate_String(PetscViewer v)
126: {
127:   PetscViewer_String *vstr;

129:   PetscFunctionBegin;
130:   v->ops->destroy          = PetscViewerDestroy_String;
131:   v->ops->view             = NULL;
132:   v->ops->flush            = NULL;
133:   v->ops->getsubviewer     = PetscViewerGetSubViewer_String;
134:   v->ops->restoresubviewer = PetscViewerRestoreSubViewer_String;
135:   PetscCall(PetscNew(&vstr));
136:   v->data      = (void *)vstr;
137:   vstr->string = NULL;
138:   PetscFunctionReturn(PETSC_SUCCESS);
139: }

141: /*@C

143:   PetscViewerStringGetStringRead - Returns the string that a `PETSCVIEWERSTRING` uses

145:   Logically Collective

147:   Input Parameter:
148: . viewer - `PETSCVIEWERSTRING` viewer

150:   Output Parameters:
151: + string - the string, optional use NULL if you do not need
152: - len    - the length of the string, optional use NULL if you do

154:   Level: advanced

156:   Note:
157:   Do not write to the string nor free it

159: .seealso: [](sec_viewers), `PetscViewerStringOpen()`, `PETSCVIEWERSTRING`, `PetscViewerStringSetString()`, `PetscViewerStringSPrintf()`,
160:           `PetscViewerStringSetOwnString()`
161: @*/
162: PetscErrorCode PetscViewerStringGetStringRead(PetscViewer viewer, const char *string[], size_t *len)
163: {
164:   PetscViewer_String *vstr = (PetscViewer_String *)viewer->data;
165:   PetscBool           isstring;

167:   PetscFunctionBegin;
169:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSTRING, &isstring));
170:   PetscCheck(isstring, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Only for PETSCVIEWERSTRING");
171:   if (string) *string = vstr->string;
172:   if (len) *len = vstr->maxlen;
173:   PetscFunctionReturn(PETSC_SUCCESS);
174: }

176: /*@C

178:   PetscViewerStringSetString - sets the string that a string viewer will print to

180:   Logically Collective

182:   Input Parameters:
183: + viewer - string viewer you wish to attach string to
184: . string - the string to print data into
185: - len    - the length of the string

187:   Level: advanced

189:   Note:
190:   The function does not copy the string, it uses it directly therefore you cannot free
191:   the string until the viewer is destroyed. If you call `PetscViewerStringSetOwnString()` the ownership
192:   passes to the viewer and it will be responsible for freeing it. In this case the string must be
193:   obtained with `PetscMalloc()`.

195: .seealso: [](sec_viewers), `PetscViewerStringOpen()`, `PETSCVIEWERSTRING`, `PetscViewerStringGetStringRead()`, `PetscViewerStringSPrintf()`,
196:           `PetscViewerStringSetOwnString()`
197: @*/
198: PetscErrorCode PetscViewerStringSetString(PetscViewer viewer, char string[], size_t len)
199: {
200:   PetscViewer_String *vstr = (PetscViewer_String *)viewer->data;
201:   PetscBool           isstring;

203:   PetscFunctionBegin;
205:   PetscAssertPointer(string, 2);
206:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSTRING, &isstring));
207:   if (!isstring) PetscFunctionReturn(PETSC_SUCCESS);
208:   PetscCheck(len > 2, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "String must have length at least 2");

210:   PetscCall(PetscArrayzero(string, len));
211:   vstr->string = string;
212:   vstr->head   = string;
213:   vstr->curlen = 0;
214:   vstr->maxlen = len;
215:   PetscFunctionReturn(PETSC_SUCCESS);
216: }

218: /*@C

220:   PetscViewerStringSetOwnString - tells the viewer that it now owns the string and is responsible for freeing it

222:   Logically Collective

224:   Input Parameter:
225: . viewer - string viewer

227:   Level: advanced

229:   Note:
230:   If you call this the string must have been obtained with `PetscMalloc()` and you cannot free the string

232: .seealso: [](sec_viewers), `PetscViewerStringOpen()`, `PETSCVIEWERSTRING`, `PetscViewerStringGetStringRead()`, `PetscViewerStringSPrintf()`,
233:           `PetscViewerStringSetString()`
234: @*/
235: PetscErrorCode PetscViewerStringSetOwnString(PetscViewer viewer)
236: {
237:   PetscViewer_String *vstr = (PetscViewer_String *)viewer->data;
238:   PetscBool           isstring;

240:   PetscFunctionBegin;
242:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSTRING, &isstring));
243:   if (!isstring) PetscFunctionReturn(PETSC_SUCCESS);

245:   vstr->ownstring = PETSC_TRUE;
246:   PetscFunctionReturn(PETSC_SUCCESS);
247: }