1 /*
2 * Copyright (c) 2000-2002, 2006 Sendmail, Inc. and its suppliers.
3 * All rights reserved.
4 * Copyright (c) 1990, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek.
9 *
10 * By using this file, you agree to the terms and conditions set
11 * forth in the LICENSE file which can be found at the top level of
12 * the sendmail distribution.
13 */
14
15 #include <sm/gen.h>
16 SM_RCSID("@(#)$Id: findfp.c,v 1.67 2006/08/28 21:24:46 ca Exp $")
17 #include <stdlib.h>
18 #include <unistd.h>
19 #include <sys/param.h>
20 #include <errno.h>
21 #include <string.h>
22 #include <syslog.h>
23 #include <sm/io.h>
24 #include <sm/assert.h>
25 #include <sm/heap.h>
26 #include <sm/string.h>
27 #include <sm/conf.h>
28 #include "local.h"
29 #include "glue.h"
30
31 bool Sm_IO_DidInit; /* IO system has been initialized? */
32
33 const char SmFileMagic[] = "sm_file";
34
35 /* An open type to map to fopen()-like behavior */
36 SM_FILE_T SmFtStdio_def =
37 {SmFileMagic, 0, 0, 0, (SMRW|SMFBF), -1, {0, 0}, 0, 0, 0,
38 sm_stdclose, sm_stdread, sm_stdseek, sm_stdwrite,
39 sm_stdopen, sm_stdsetinfo, sm_stdgetinfo, SM_TIME_FOREVER,
40 SM_TIME_BLOCK, "stdio" };
41
42 /* An open type to map to fdopen()-like behavior */
43 SM_FILE_T SmFtStdiofd_def =
44 {SmFileMagic, 0, 0, 0, (SMRW|SMFBF), -1, {0, 0}, 0, 0, 0,
45 sm_stdclose, sm_stdread, sm_stdseek, sm_stdwrite,
46 sm_stdfdopen, sm_stdsetinfo, sm_stdgetinfo, SM_TIME_FOREVER,
47 SM_TIME_BLOCK, "stdiofd" };
48
49 /* A string file type */
50 SM_FILE_T SmFtString_def =
51 {SmFileMagic, 0, 0, 0, (SMRW|SMNBF), -1, {0, 0}, 0, 0, 0,
52 sm_strclose, sm_strread, sm_strseek, sm_strwrite,
53 sm_stropen, sm_strsetinfo, sm_strgetinfo, SM_TIME_FOREVER,
54 SM_TIME_BLOCK, "string" };
55
56 #if 0
57 /* A file type for syslog communications */
58 SM_FILE_T SmFtSyslog_def =
59 {SmFileMagic, 0, 0, 0, (SMRW|SMNBF), -1, {0, 0}, 0, 0, 0,
60 sm_syslogclose, sm_syslogread, sm_syslogseek, sm_syslogwrite,
61 sm_syslogopen, sm_syslogsetinfo, sm_sysloggetinfo, SM_TIME_FOREVER,
62 SM_TIME_BLOCK, "syslog" };
63 #endif /* 0 */
64
65 #define NDYNAMIC 10 /* add ten more whenever necessary */
66
67 #define smio(flags, file, name) \
68 {SmFileMagic, 0, 0, 0, flags, file, {0}, 0, SmIoF+file, 0, \
69 sm_stdclose, sm_stdread, sm_stdseek, sm_stdwrite, \
70 sm_stdopen, sm_stdsetinfo, sm_stdgetinfo, SM_TIME_FOREVER, \
71 SM_TIME_BLOCK, name}
72
73 /* sm_magic p r w flags file bf lbfsize cookie ival */
74 #define smstd(flags, file, name) \
75 {SmFileMagic, 0, 0, 0, flags, -1, {0}, 0, 0, file, \
76 sm_stdioclose, sm_stdioread, sm_stdioseek, sm_stdiowrite, \
77 sm_stdioopen, sm_stdiosetinfo, sm_stdiogetinfo, SM_TIME_FOREVER,\
78 SM_TIME_BLOCK, name}
79
80 /* A file type for interfacing to stdio FILE* streams. */
81 SM_FILE_T SmFtRealStdio_def = smstd(SMRW|SMNBF, -1, "realstdio");
82
83 /* the usual - (stdin + stdout + stderr) */
84 static SM_FILE_T usual[SM_IO_OPEN_MAX - 3];
85 static struct sm_glue smuglue = { 0, SM_IO_OPEN_MAX - 3, usual };
86
87 /* List of builtin automagically already open file pointers */
88 SM_FILE_T SmIoF[6] =
89 {
90 smio(SMRD|SMLBF, SMIOIN_FILENO, "smioin"), /* smioin */
91 smio(SMWR|SMLBF, SMIOOUT_FILENO, "smioout"), /* smioout */
92 smio(SMWR|SMNBF, SMIOERR_FILENO, "smioerr"), /* smioerr */
93 smstd(SMRD|SMNBF, SMIOIN_FILENO, "smiostdin"), /* smiostdin */
94 smstd(SMWR|SMNBF, SMIOOUT_FILENO, "smiostdout"),/* smiostdout */
95 smstd(SMWR|SMNBF, SMIOERR_FILENO, "smiostderr") /* smiostderr */
96 };
97
98 /* Structure containing list of currently open file pointers */
99 struct sm_glue smglue = { &smuglue, 3, SmIoF };
100
101 /*
102 ** SM_MOREGLUE -- adds more space for open file pointers
103 **
104 ** Parameters:
105 ** n -- number of new spaces for file pointers
106 **
107 ** Returns:
108 ** Raises an exception if no more memory.
109 ** Otherwise, returns a pointer to new spaces.
110 */
111
112 static struct sm_glue *sm_moreglue_x __P((int));
113 static SM_FILE_T empty;
114
115 static struct sm_glue *
sm_moreglue_x(n)116 sm_moreglue_x(n)
117 register int n;
118 {
119 register struct sm_glue *g;
120 register SM_FILE_T *p;
121
122 g = (struct sm_glue *) sm_pmalloc_x(sizeof(*g) + SM_ALIGN_BITS +
123 n * sizeof(SM_FILE_T));
124 p = (SM_FILE_T *) SM_ALIGN(g + 1);
125 g->gl_next = NULL;
126 g->gl_niobs = n;
127 g->gl_iobs = p;
128 while (--n >= 0)
129 *p++ = empty;
130 return g;
131 }
132
133 /*
134 ** SM_FP -- allocate and initialize an SM_FILE structure
135 **
136 ** Parameters:
137 ** t -- file type requested to be opened.
138 ** flags -- control flags for file type behavior
139 ** oldfp -- file pointer to reuse if available (optional)
140 **
141 ** Returns:
142 ** Raises exception on memory exhaustion.
143 ** Aborts if type is invalid.
144 ** Otherwise, returns file pointer for requested file type.
145 */
146
147 SM_FILE_T *
sm_fp(t,flags,oldfp)148 sm_fp(t, flags, oldfp)
149 const SM_FILE_T *t;
150 const int flags;
151 SM_FILE_T *oldfp;
152 {
153 register SM_FILE_T *fp;
154 register int n;
155 register struct sm_glue *g;
156
157 SM_REQUIRE(t->f_open && t->f_close && (t->f_read || t->f_write));
158
159 if (!Sm_IO_DidInit)
160 sm_init();
161
162 if (oldfp != NULL)
163 {
164 fp = oldfp;
165 goto found; /* for opening reusing an 'fp' */
166 }
167
168 for (g = &smglue;; g = g->gl_next)
169 {
170 for (fp = g->gl_iobs, n = g->gl_niobs; --n >= 0; fp++)
171 if (fp->sm_magic == NULL)
172 goto found;
173 if (g->gl_next == NULL)
174 g->gl_next = sm_moreglue_x(NDYNAMIC);
175 }
176 found:
177 fp->sm_magic = SmFileMagic; /* 'fp' now valid and in-use */
178 fp->f_p = NULL; /* no current pointer */
179 fp->f_w = 0; /* nothing to write */
180 fp->f_r = 0; /* nothing to read */
181 fp->f_flags = flags;
182 fp->f_file = -1; /* no file */
183 fp->f_bf.smb_base = NULL; /* no buffer */
184 fp->f_bf.smb_size = 0; /* no buffer size with no buffer */
185 fp->f_lbfsize = 0; /* not line buffered */
186 fp->f_flushfp = NULL; /* no associated flush file */
187
188 fp->f_cookie = fp; /* default: *open* overrides cookie setting */
189 fp->f_close = t->f_close; /* assign close function */
190 fp->f_read = t->f_read; /* assign read function */
191 fp->f_seek = t->f_seek; /* assign seek function */
192 fp->f_write = t->f_write; /* assign write function */
193 fp->f_open = t->f_open; /* assign open function */
194 fp->f_setinfo = t->f_setinfo; /* assign setinfo function */
195 fp->f_getinfo = t->f_getinfo; /* assign getinfo function */
196 fp->f_type = t->f_type; /* file type */
197
198 fp->f_ub.smb_base = NULL; /* no ungetc buffer */
199 fp->f_ub.smb_size = 0; /* no size for no ungetc buffer */
200
201 if (fp->f_timeout == SM_TIME_DEFAULT)
202 fp->f_timeout = SM_TIME_FOREVER;
203 else
204 fp->f_timeout = t->f_timeout; /* traditional behavior */
205 fp->f_timeoutstate = SM_TIME_BLOCK; /* by default */
206
207 return fp;
208 }
209
210 /*
211 ** SM_CLEANUP -- cleanup function when exit called.
212 **
213 ** This function is registered via atexit().
214 **
215 ** Parameters:
216 ** none
217 **
218 ** Returns:
219 ** nothing.
220 **
221 ** Side Effects:
222 ** flushes open files before they are forced closed
223 */
224
225 void
sm_cleanup()226 sm_cleanup()
227 {
228 int timeout = SM_TIME_DEFAULT;
229
230 (void) sm_fwalk(sm_flush, &timeout); /* `cheating' */
231 }
232
233 /*
234 ** SM_INIT -- called whenever sm_io's internal variables must be set up.
235 **
236 ** Parameters:
237 ** none
238 **
239 ** Returns:
240 ** none
241 **
242 ** Side Effects:
243 ** Registers sm_cleanup() using atexit().
244 */
245
246 void
sm_init()247 sm_init()
248 {
249 if (Sm_IO_DidInit) /* paranoia */
250 return;
251
252 /* more paranoia: initialize pointers in a static variable */
253 empty.f_type = NULL;
254 empty.sm_magic = NULL;
255
256 /* make sure we clean up on exit */
257 atexit(sm_cleanup); /* conservative */
258 Sm_IO_DidInit = true;
259 }
260
261 /*
262 ** SM_IO_SETINFO -- change info for an open file type (fp)
263 **
264 ** The generic SM_IO_WHAT_VECTORS is auto supplied for all file types.
265 ** If the request is to set info other than SM_IO_WHAT_VECTORS then
266 ** the request is passed on to the file type's specific setinfo vector.
267 ** WARNING: this is working on an active/open file type.
268 **
269 ** Parameters:
270 ** fp -- file to make the setting on
271 ** what -- type of information to set
272 ** valp -- structure to obtain info from
273 **
274 ** Returns:
275 ** 0 on success
276 ** -1 on error and sets errno:
277 ** - when what != SM_IO_WHAT_VECTORS and setinfo vector
278 ** not set
279 ** - when vectored setinfo returns -1
280 */
281
282 int
sm_io_setinfo(fp,what,valp)283 sm_io_setinfo(fp, what, valp)
284 SM_FILE_T *fp;
285 int what;
286 void *valp;
287 {
288 SM_FILE_T *v = (SM_FILE_T *) valp;
289
290 SM_REQUIRE_ISA(fp, SmFileMagic);
291 switch (what)
292 {
293 case SM_IO_WHAT_VECTORS:
294
295 /*
296 ** This is the "generic" available for all.
297 ** This allows the function vectors to be replaced
298 ** while the file type is active.
299 */
300
301 fp->f_close = v->f_close;
302 fp->f_read = v->f_read;
303 fp->f_seek = v->f_seek;
304 fp->f_write = v->f_write;
305 fp->f_open = v->f_open;
306 fp->f_setinfo = v->f_setinfo;
307 fp->f_getinfo = v->f_getinfo;
308 sm_free(fp->f_type);
309 fp->f_type = sm_strdup_x(v->f_type);
310 return 0;
311 case SM_IO_WHAT_TIMEOUT:
312 fp->f_timeout = *((int *)valp);
313 return 0;
314 }
315
316 /* Otherwise the vector will check it out */
317 if (fp->f_setinfo == NULL)
318 {
319 errno = EINVAL;
320 return -1;
321 }
322 else
323 return (*fp->f_setinfo)(fp, what, valp);
324 }
325
326 /*
327 ** SM_IO_GETINFO -- get information for an active file type (fp)
328 **
329 ** This function supplies for all file types the answers for the
330 ** three requests SM_IO_WHAT_VECTORS, SM_IO_WHAT_TYPE and
331 ** SM_IO_WHAT_ISTYPE. Other requests are handled by the getinfo
332 ** vector if available for the open file type.
333 ** SM_IO_WHAT_VECTORS returns information for the file pointer vectors.
334 ** SM_IO_WHAT_TYPE returns the type identifier for the file pointer
335 ** SM_IO_WHAT_ISTYPE returns >0 if the passed in type matches the
336 ** file pointer's type.
337 ** SM_IO_IS_READABLE returns 1 if there is data available for reading,
338 ** 0 otherwise.
339 **
340 ** Parameters:
341 ** fp -- file pointer for active file type
342 ** what -- type of information request
343 ** valp -- structure to place obtained info into
344 **
345 ** Returns:
346 ** -1 on error and sets errno:
347 ** - when valp==NULL and request expects otherwise
348 ** - when request is not SM_IO_WHAT_VECTORS and not
349 ** SM_IO_WHAT_TYPE and not SM_IO_WHAT_ISTYPE
350 ** and getinfo vector is NULL
351 ** - when getinfo type vector returns -1
352 ** >=0 on success
353 */
354
355 int
sm_io_getinfo(fp,what,valp)356 sm_io_getinfo(fp, what, valp)
357 SM_FILE_T *fp;
358 int what;
359 void *valp;
360 {
361 SM_FILE_T *v = (SM_FILE_T *) valp;
362
363 SM_REQUIRE_ISA(fp, SmFileMagic);
364
365 switch (what)
366 {
367 case SM_IO_WHAT_VECTORS:
368 if (valp == NULL)
369 {
370 errno = EINVAL;
371 return -1;
372 }
373
374 /* This is the "generic" available for all */
375 v->f_close = fp->f_close;
376 v->f_read = fp->f_read;
377 v->f_seek = fp->f_seek;
378 v->f_write = fp->f_write;
379 v->f_open = fp->f_open;
380 v->f_setinfo = fp->f_setinfo;
381 v->f_getinfo = fp->f_getinfo;
382 v->f_type = fp->f_type;
383 return 0;
384
385 case SM_IO_WHAT_TYPE:
386 if (valp == NULL)
387 {
388 errno = EINVAL;
389 return -1;
390 }
391 valp = sm_strdup_x(fp->f_type);
392 return 0;
393
394 case SM_IO_WHAT_ISTYPE:
395 if (valp == NULL)
396 {
397 errno = EINVAL;
398 return -1;
399 }
400 return strcmp(fp->f_type, valp) == 0;
401
402 case SM_IO_IS_READABLE:
403
404 /* if there is data in the buffer, it must be readable */
405 if (fp->f_r > 0)
406 return 1;
407
408 /* otherwise query the underlying file */
409 break;
410
411 case SM_IO_WHAT_TIMEOUT:
412 *((int *) valp) = fp->f_timeout;
413 return 0;
414
415 case SM_IO_WHAT_FD:
416 if (fp->f_file > -1)
417 return fp->f_file;
418
419 /* try the file type specific getinfo to see if it knows */
420 break;
421 }
422
423 /* Otherwise the vector will check it out */
424 if (fp->f_getinfo == NULL)
425 {
426 errno = EINVAL;
427 return -1;
428 }
429 return (*fp->f_getinfo)(fp, what, valp);
430 }
431