source: git/src/message.c @ 2a03043

RELEASE/1.0RELEASE/1.1RELEASE/1.2debug-cidebug-ci-sanitisersfaster-cavernloglog-selectstereostereo-2025walls-datawalls-data-hanging-as-warningwarn-only-for-hanging-survey
Last change on this file since 2a03043 was 32232b2, checked in by Olly Betts <olly@…>, 26 years ago

check env var LANG if SURVEXLANG not set

git-svn-id: file:///home/survex-svn/survex/trunk@289 4b37db11-9a0c-4f06-9ece-9ab7cdaee568

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File size: 15.9 KB
RevLine 
[db75e18]1/* > message.c
2 * Fairly general purpose message and error routines
3 * Copyright (C) 1993-1998 Olly Betts
[60f7018]4 */
5
[55de792]6/*#define DEBUG 1*/
7
[db75e18]8#ifdef HAVE_CONFIG_H
9# include <config.h>
10#endif
[60f7018]11
12#include <stdio.h>
13#include <stdlib.h>
14#include <string.h>
15#include <ctype.h>
16#include <limits.h>
17#include <errno.h>
18
19#include "whichos.h"
[4432f2e]20#include "filename.h"
21#include "message.h"
[60f7018]22#include "osdepend.h"
23#include "filelist.h"
24#include "debug.h"
25
26#ifdef HAVE_SIGNAL
27# ifdef HAVE_SETJMP
28#  include <setjmp.h>
29static jmp_buf jmpbufSignal;
30#  include <signal.h>
31# else
32#  undef HAVE_SIGNAL
33# endif
34#endif
35
36/* This is the name of the default language -- set like this so folks can
[4432f2e]37 * add (for eg) -DDEFAULTLANG="fr" to UFLG in the makefile
[db75e18]38 * FIXME - update wrt automake/autoconf
[60f7018]39 */
40#ifndef DEFAULTLANG
[4432f2e]41# define DEFAULTLANG "en"
[60f7018]42#endif
43
44/* For funcs which want to be immune from messing around with different
45 * calling conventions */
46#ifndef CDECL
[2ca296b]47# define CDECL
[60f7018]48#endif
49
50static int cWarnings = 0; /* keep track of how many warnings we've given */
51static int cErrors = 0;   /* and how many (non-fatal) errors */
52
53extern int error_summary(void) {
[db75e18]54   fprintf(STDERR, msg(/*There were %d warning(s) and %d non-fatal error(s).*/16),
55           cWarnings, cErrors);
[60f7018]56   fputnl(STDERR);
[db75e18]57   return (cErrors ? EXIT_FAILURE : EXIT_SUCCESS);
[60f7018]58}
59
60/* in case osmalloc() fails before szAppNameCopy is set up */
[b8d27ca]61const char *szAppNameCopy = "anonymous program";
[60f7018]62
63/* error code for failed osmalloc and osrealloc calls */
[db75e18]64static void
65outofmem(OSSIZE_T size)
66{
67   fatalerror(1/*Out of memory (couldn't find %lu bytes).*/, (unsigned long)size);
[60f7018]68}
69
[a420b49]70#ifdef TOMBSTONES
71#define TOMBSTONE_SIZE 16
72static char tombstone[TOMBSTONE_SIZE] = "012345\xfftombstone";
73#endif
74
[60f7018]75/* malloc with error catching if it fails. Also allows us to write special
76 * versions easily eg for DOS EMS or MS Windows.
77 */
[db75e18]78extern void FAR *
79osmalloc(OSSIZE_T size)
80{
[60f7018]81   void FAR *p;
[a420b49]82#ifdef TOMBSTONES
83   size += TOMBSTONE_SIZE * 2;
84   p = malloc(size);
85#else
[db75e18]86   p = xosmalloc(size);
[a420b49]87#endif
[2ca296b]88   if (p == NULL) outofmem(size);
[a420b49]89#ifdef TOMBSTONES
90printf("osmalloc truep=%p truesize=%d\n",p,size);
91   memcpy(p, tombstone, TOMBSTONE_SIZE);
92   memcpy(p + size - TOMBSTONE_SIZE, tombstone, TOMBSTONE_SIZE);
93   *(size_t *)p = size;
94   p += TOMBSTONE_SIZE;
95#endif
[60f7018]96   return p;
97}
98
99/* realloc with error catching if it fails. */
[db75e18]100extern void FAR *
101osrealloc(void *p, OSSIZE_T size)
102{
[a420b49]103   /* some pre-ANSI realloc implementations don't cope with a NULL pointer */
104   if (p == NULL) {
105      p = xosmalloc(size);
106   } else {
107#ifdef TOMBSTONES
108      int true_size;
109      size += TOMBSTONE_SIZE * 2;
110      p -= TOMBSTONE_SIZE;
111      true_size = *(size_t *)p;
112printf("osrealloc (in truep=%p truesize=%d)\n",p,true_size);
113      if (memcmp(p + sizeof(size_t), tombstone + sizeof(size_t),
114                 TOMBSTONE_SIZE - sizeof(size_t)) != 0) {
115         printf("start tombstone for block %p, size %d corrupted!",
116                p + TOMBSTONE_SIZE, true_size - TOMBSTONE_SIZE * 2);     
117      }
118      if (memcmp(p + true_size - TOMBSTONE_SIZE, tombstone,
119                 TOMBSTONE_SIZE) != 0) {
120         printf("end tombstone for block %p, size %d corrupted!",
121                p + TOMBSTONE_SIZE, true_size - TOMBSTONE_SIZE * 2);     
122      }
123      p = realloc(p, size);
124      if (p == NULL) outofmem(size);
125printf("osrealloc truep=%p truesize=%d\n",p,size);
126      memcpy(p, tombstone, TOMBSTONE_SIZE);
127      memcpy(p + size - TOMBSTONE_SIZE, tombstone, TOMBSTONE_SIZE);
128      *(size_t *)p = size;
129      p += TOMBSTONE_SIZE;
130#else
131      p = xosrealloc(p, size);
132#endif
133   }
[2ca296b]134   if (p == NULL) outofmem(size);
[60f7018]135   return p;
136}
137
[db75e18]138extern void FAR *
139osstrdup(const char *str)
140{
[60f7018]141   char *p;
[db75e18]142   OSSIZE_T len;
143   len = strlen(str) + 1;
[2ca296b]144   p = osmalloc(len);
[db75e18]145   memcpy(p, str, len);
[60f7018]146   return p;
147}
148
[a420b49]149/* osfree is usually just a macro in osalloc.h */
150#ifdef TOMBSTONES
151extern void
152osfree(void *p)
153{
154   int true_size;
155   if (!p) return;
156   p -= TOMBSTONE_SIZE;
157   true_size = *(size_t *)p;
158printf("osfree truep=%p truesize=%d\n",p,true_size);
159   if (memcmp(p + sizeof(size_t), tombstone + sizeof(size_t),
160              TOMBSTONE_SIZE - sizeof(size_t)) != 0) {
161      printf("start tombstone for block %p, size %d corrupted!",
162             p + TOMBSTONE_SIZE, true_size - TOMBSTONE_SIZE * 2);     
163   }
164   if (memcmp(p + true_size - TOMBSTONE_SIZE, tombstone,
165              TOMBSTONE_SIZE) != 0) {
166      printf("end tombstone for block %p, size %d corrupted!",
167             p + TOMBSTONE_SIZE, true_size - TOMBSTONE_SIZE * 2);     
168   }
169   free(p);
170}
171#endif
[60f7018]172
173#ifdef HAVE_SIGNAL
174
175static int sigReceived;
176
177/* for systems not using autoconf, assume the signal handler returns void
178 * unless specified elsewhere */
179#ifndef RETSIGTYPE
[2ca296b]180# define RETSIGTYPE void
[60f7018]181#endif
182
183static CDECL RETSIGTYPE FAR report_sig( int sig ) {
[db75e18]184   sigReceived = sig;
[2ca296b]185   longjmp(jmpbufSignal, 1);
[60f7018]186}
187
[db75e18]188static void
189init_signals(void)
190{
[60f7018]191   int en;
192   if (!setjmp(jmpbufSignal)) {
[45d2d25]193#if 0 /* FIXME: disable for now so we get a core dump */
[db75e18]194      signal(SIGABRT, report_sig); /* abnormal termination eg abort() */
195      signal(SIGFPE,  report_sig); /* arithmetic error eg /0 or overflow */
196      signal(SIGILL,  report_sig); /* illegal function image eg illegal instruction */
197      signal(SIGSEGV, report_sig); /* illegal storage access eg access outside memory limits */
198#endif
199      signal(SIGINT,  report_sig); /* interactive attention eg interrupt */
200      signal(SIGTERM, report_sig); /* termination request sent to program */
[60f7018]201# ifdef SIGSTAK /* only on RISC OS AFAIK */
[db75e18]202      signal(SIGSTAK, report_sig); /* stack overflow */
[60f7018]203# endif
204      return;
205   }
[db75e18]206
[60f7018]207   switch (sigReceived) {
[db75e18]208   case SIGABRT: en=90; break;
209   case SIGFPE:  en=91; break;
210   case SIGILL:  en=92; break;
211   case SIGINT:  en=93; break;
212   case SIGSEGV: en=94; break;
213   case SIGTERM: en=95; break;
[60f7018]214# ifdef SIGSTAK
[db75e18]215   case SIGSTAK: en=96; break;
[60f7018]216# endif
[db75e18]217   default:      en=97; break;
[60f7018]218   }
[db75e18]219   fputsnl(msg(en), STDERR);
[60f7018]220   if (errno >= 0) {
221# ifdef HAVE_STRERROR
[db75e18]222      fputsnl(strerror(errno), STDERR);
[60f7018]223# elif defined(HAVE_SYS_ERRLIST)
[db75e18]224      if (errno < sys_nerr) fputsnl(STDERR, sys_errlist[errno]);
[60f7018]225# elif defined(HAVE_PERROR)
226      perror(NULL); /* always goes to stderr */
227      /* if (arg!=NULL && *arg!='\0') fputs("<arg>: <err>\n",stderr); */
228      /* else fputs("<err>\n",stderr); */
229# else
[db75e18]230      fprintf(STDERR, "error code %d\n", errno);
[60f7018]231# endif
232   }
[db75e18]233   /* Any signals apart from SIGINT and SIGTERM suggest a bug */
234   if (sigReceived != SIGINT && sigReceived != SIGTERM)
235      fatalerror(/*Bug in program detected! Please report this to the authors*/11);
236
[60f7018]237   exit(EXIT_FAILURE);
238}
239#endif
240
241#define CHARSET_BAD       -1
242#define CHARSET_USASCII    0
243#define CHARSET_ISO_8859_1 1
244#define CHARSET_DOSCP850   2
245#define CHARSET_RISCOS31   3
246static int default_charset( void ) {
247#ifdef ISO8859_1
248   return CHARSET_ISO_8859_1;
249#elif (OS==RISCOS)
[2ca296b]250/* RISCOS 3.1 and above CHARSET_RISCOS31 (ISO_8859_1 + extras in 128-159)
251 * RISCOS < 3.1 is ISO_8859_1 !HACK! */
252   return CHARSET_RISCOS31;
[60f7018]253#elif (OS==MSDOS)
254   return CHARSET_DOSCP850;
255#else
[2ca296b]256   return CHARSET_ISO_8859_1; /* Look at env var CHARSET ? !HACK! */
[60f7018]257#endif
258}
259
[48e4121]260#if (OS==MSDOS)
[db75e18]261static int
262xlate_dos_cp850(int unicode)
263{
[48e4121]264   switch (unicode) {
[d41b1353]265#include "uni2dos.h"
[48e4121]266   }
267   return 0;
268}
269#endif
270
[db75e18]271static int
[55de792]272add_unicode(int charset, unsigned char *p, int value)
[db75e18]273{
[55de792]274#ifdef DEBUG
275   fprintf(stderr, "add_unicode(%d, %p, %d)\n", charset, p, value);
276#endif
[4432f2e]277   if (value == 0) return 0;
[48e4121]278   switch (charset) {
[db75e18]279   case CHARSET_USASCII:
[48e4121]280      if (value < 128) {
281         *p = value;
282         return 1;
283      }
284      break;
[db75e18]285   case CHARSET_ISO_8859_1:
[48e4121]286#if (OS==RISCOS)
[db75e18]287   case CHARSET_RISCOS31: /* RISC OS 3.1 has a few extras in 128-159 */
[48e4121]288#endif
289      if (value < 256) {
290         *p = value;
291         return 1;
292      }
293#if (OS==RISCOS)
[db75e18]294      /* FIXME: if OS version >= 3.1 handle extras here */
295      /* RISC OS 3.1 (and later) extensions to ISO-8859-1:
296       * \^y = \x86
297       * \^Y = \x85
298       * \^w = \x82
299       * \^W = \x81
300       * \oe = \x9b
301       * \OE = \x9a
302       */
[48e4121]303#endif
304      break;
305#if (OS==MSDOS)
[db75e18]306   case CHARSET_DOSCP850:
[48e4121]307      value = xlate_dos_cp850(value);
308      if (value) {
309         *p = value;
310         return 1;
311      }
312      break;
313#endif
[4432f2e]314   }
[f1a5201]315   return 0;
[4432f2e]316}
317
[f2a6ce4]318/* fall back on looking in the current directory */
319static const char *pth_cfg_files = "";
320
[db75e18]321static int num_msgs = 0;
[55de792]322static char **msg_array = NULL;
[db75e18]323
324static void
325parse_msg_file(int charset_code)
326{
327   FILE *fh;
328   unsigned char header[20];
329   const char *lang;
[4432f2e]330   int i;
[db75e18]331   unsigned len;
[55de792]332   unsigned char *p;
333   
334#ifdef DEBUG
335   fprintf(stderr, "parse_msg_file(%d)\n", charset_code);
336#endif
[db75e18]337
338   lang = getenv("SURVEXLANG");
[55de792]339#ifdef DEBUG
340   fprintf(stderr, "lang = %p (= \"%s\")\n", lang, lang?lang:"(null)");
341#endif
342   
[32232b2]343   if (!lang || !*lang) {
344      lang = getenv("LANG");
345      if (!lang || !*lang) lang = DEFAULTLANG;
346   }
[55de792]347#ifdef DEBUG
348   fprintf(stderr, "lang = %p (= \"%s\")\n", lang, lang?lang:"(null)");
349#endif
[db75e18]350
351#if 1
352   /* backward compatibility - FIXME deprecate? */
[d41b1353]353   if (strcasecmp(lang, "engi") == 0) {
[db75e18]354      lang = "en";
[d41b1353]355   } else if (strcasecmp(lang, "engu") == 0) {
[db75e18]356      lang = "en-us";
[d41b1353]357   } else if (strcasecmp(lang, "fren") == 0) {
[db75e18]358      lang = "fr";
[d41b1353]359   } else if (strcasecmp(lang, "germ") == 0) {
[db75e18]360      lang = "de";
[d41b1353]361   } else if (strcasecmp(lang, "ital") == 0) {
[db75e18]362      lang = "it";
[d41b1353]363   } else if (strcasecmp(lang, "span") == 0) {
[db75e18]364      lang = "es";
[d41b1353]365   } else if (strcasecmp(lang, "cata") == 0) {
[db75e18]366      lang = "ca";
[d41b1353]367   } else if (strcasecmp(lang, "port") == 0) {
[db75e18]368      lang = "pt";
[48e4121]369   }
[db75e18]370#endif
[55de792]371#ifdef DEBUG
372   fprintf(stderr, "lang = %p (= \"%s\")\n", lang, lang?lang:"(null)");
373#endif
[db75e18]374
[f2a6ce4]375   fh = fopenWithPthAndExt(pth_cfg_files, lang, EXT_SVX_MSG, "rb", NULL);
[db75e18]376
377   if (!fh) {
378      /* e.g. if 'en-COCKNEY' is unknown, see if we know 'en' */
379      if (strlen(lang) > 3 && lang[2] == '-') {
380         char lang_generic[3];
381         lang_generic[0] = lang[0];
382         lang_generic[1] = lang[1];
383         lang_generic[2] = '\0';
[f2a6ce4]384         fh = fopenWithPthAndExt(pth_cfg_files, lang_generic, EXT_SVX_MSG,
385                                 "rb", NULL);
[db75e18]386      }
[48e4121]387   }
[db75e18]388
389   if (!fh) {
390      /* no point extracting this error, as it won't get used if file opens */
391      fprintf(STDERR, "Can't open message file '%s' using path '%s'\n",
[f2a6ce4]392              lang, pth_cfg_files);
[db75e18]393      exit(EXIT_FAILURE);
[4432f2e]394   }
[db75e18]395
396   if (fread(header, 1, 20, fh) < 20 ||
397       memcmp(header, "Svx\nMsg\r\n\xfe\xff", 12) != 0) {
398      /* no point extracting this error, as it won't get used if file opens */
399      fprintf(STDERR, "Problem with message file '%s'\n", lang);
400      exit(EXIT_FAILURE);
401   }
402
403   if (header[12] != 0) {
404      /* no point extracting this error, as it won't get used if file opens */
405      fprintf(STDERR, "I don't understand this message file version\n");
406      exit(EXIT_FAILURE);
407   }
408
409   num_msgs = (header[14] << 8) | header[15];
410
411   len = 0;
412   for (i = 16; i < 20; i++) len = (len << 8) | header[i];
413
[55de792]414   p = osmalloc(len);
415   if (fread(p, 1, len, fh) < len) {
[db75e18]416      /* no point extracting this error - it won't get used once file's read */
417      fprintf(STDERR, "Message file truncated?\n");
418      exit(EXIT_FAILURE);
419   }
[a420b49]420   fclose(fh);
[db75e18]421
[55de792]422#ifdef DEBUG
423   fprintf(stderr, "lang = '%s', num_msgs = %d, len = %d\n", lang, num_msgs, len);
424#endif
425
426   msg_array = osmalloc(sizeof(char *) * num_msgs);
427
[db75e18]428   for (i = 0; i < num_msgs; i++) {
[55de792]429      unsigned char *to = p;
[db75e18]430      int ch;
[55de792]431      msg_array[i] = (char *)p;
[db75e18]432      while ((ch = *p++) != 0) {
433         /* A byte in the range 0x80-0xbf or 0xf0-0xff isn't valid in
434          * this state, (0xf0-0xfd mean values > 0xffff) so treat as
435          * literal and try to resync so we cope better when fed
436          * non-utf-8 data.  Similarly we abandon a multibyte sequence
437          * if we hit an invalid character. */
438         if (ch >= 0xc0 && ch < 0xf0) {
439            int ch1 = *p;
440            if ((ch1 & 0xc0) != 0x80) goto resync;
441               
442            if (ch < 0xe0) {
443               /* 2 byte sequence */
444               ch = ((ch & 0x1f) << 6) | (ch1 & 0x3f);
445               p++;
446            } else {
447               /* 3 byte sequence */
448               int ch2 = p[1];
449               if ((ch2 & 0xc0) != 0x80) goto resync;
450               ch = ((ch & 0x1f) << 12) | ((ch1 & 0x3f) << 6) | (ch2 & 0x3f);
451               p += 2;
452            }
453         }
454           
455         resync:
456           
457         if (ch < 127) {
458            *to++ = (char)ch;
459         } else {
460            /* FIXME this rather assumes a 2 byte UTF-8 code never
461             * transliterates to more than 2 characters */
462            to += add_unicode(charset_code, to, ch);
463         }
464      }
465      *to++ = '\0';
466   }
[4432f2e]467}
468
[f2a6ce4]469const char *
470msg_cfgpth(void)
471{
472   return pth_cfg_files;
473}
474
475void
476msg_init(const char *argv0)
[db75e18]477{
478   char *p;
479
480#ifdef HAVE_SIGNAL
481   init_signals();
482#endif
483   /* This code *should* be completely bomb-proof even if strcpy
484    * generates a signal
485    */
486   szAppNameCopy = argv0; /* FIXME... */
487   szAppNameCopy = osstrdup(argv0);
488
489   /* Look for env. var. "SURVEXHOME" or the like */
490   p = getenv("SURVEXHOME");
491   if (p && *p) {
[f2a6ce4]492      pth_cfg_files = osstrdup(p);
[18f4759]493#if (OS==UNIX) && defined(DATADIR) && defined(PACKAGE)
[a420b49]494   } else {
495      /* under Unix, we compile in the configured path */
[18f4759]496      pth_cfg_files = DATADIR "/" PACKAGE;
[a420b49]497#else
[db75e18]498   } else if (argv0) {
499      /* else try the path on argv[0] */
[f2a6ce4]500      pth_cfg_files = path_from_fnm(argv0);
[a420b49]501#endif
[db75e18]502   }
503
504   select_charset(default_charset());
505}
506
507/* message may be overwritten by next call (but not in current implementation) */
508extern const char *
509msg(int en)
510{
511   static const char *szBadEn = "???";
512
[55de792]513   if (!msg_array) {
[a420b49]514      if (en != 1) return szBadEn;
515      /* this should be the only message which can be requested before
516       * the message file is opened and read... */
517      return "Out of memory (couldn't find %ul bytes).\n";
[db75e18]518   }
519
520   if (en < 0 || en >= num_msgs) return szBadEn;
521
[55de792]522   return msg_array[en];
[db75e18]523}
524
525/* returns persistent copy of message */
526extern const char *
527msgPerm(int en)
528{
529   return msg(en);
530}
531
532void
533v_report(int severity, const char *fnm, int line, int en, va_list ap)
534{
535   if (fnm) {
536      fputs(fnm, STDERR);
537      if (line) fprintf(STDERR, ":%d", line);
538   } else {
539      fputs(szAppNameCopy, STDERR);
540   }   
541   fputs(": ", STDERR);
542
543   if (severity == 0) {
544      fputs(msg(/*warning*/4), STDERR);
545      fputs(": ", STDERR);
546   }
547
548   vfprintf(STDERR, msg(en), ap);
549   fputnl(STDERR);
550   
551   /* FIXME allow "warnings are errors" and/or "errors are fatal" */
552   switch (severity) {
553    case 0:
554      cWarnings++;
555      break;
556    case 1:
557      cErrors++;
558      if (cErrors == 50)
559         fatalerror_in_file(fnm, 0, /*Too many errors - giving up*/19);
560      break;
561    case 2:
562      exit(EXIT_FAILURE);
563   }
564}
565
566void
567warning(int en, ...)
568{
569   va_list ap;
570   va_start(ap, en);
571   v_report(0, NULL, 0, en, ap);
572   va_end(ap);
573}
574
575void
576error(int en, ...)
577{
578   va_list ap;
579   va_start(ap, en);
580   v_report(1, NULL, 0, en, ap);
581   va_end(ap);
582}
583
584void
585fatalerror(int en, ...)
586{
587   va_list ap;
588   va_start(ap, en);
589   v_report(2, NULL, 0, en, ap);
590   va_end(ap);
591}
592
593void
594warning_in_file(const char *fnm, int line, int en, ...)
595{
596   va_list ap;
597   va_start(ap, en);
598   v_report(0, fnm, line, en, ap);
599   va_end(ap);
600}
601
602void
603error_in_file(const char *fnm, int line, int en, ...)
604{
605   va_list ap;
606   va_start(ap, en);
607   v_report(1, fnm, line, en, ap);
608   va_end(ap);
609}
610
611void
612fatalerror_in_file(const char *fnm, int line, int en, ...)
613{
614   va_list ap;
615   va_start(ap, en);
616   v_report(2, fnm, line, en, ap);
617   va_end(ap);
618}
619
620/* Code to support switching character set at runtime (e.g. for a printer
621 * driver to support different character sets on screen and on the printer)
622 */
623typedef struct charset_li {
624   struct charset_li *next;
625   int code;
[55de792]626   char **msg_array;
[db75e18]627} charset_li;
628
629static charset_li *charset_head = NULL;
630
631static int charset = CHARSET_BAD;
632
633int
634select_charset(int charset_code)
635{
636   int old_charset = charset;
637   charset_li *p;
638
[55de792]639#ifdef DEBUG
640   fprintf(stderr, "select_charset(%d), old charset = %d\n", charset_code, charset);
641#endif
642   
[db75e18]643   charset = charset_code;
644
645   /* check if we've already parsed messages for new charset */
646   for (p = charset_head; p; p = p->next) {
[55de792]647#ifdef DEBUG
648      printf("%p: code %d msg_array %p\n", p, p->code, p->msg_array);
649#endif
[db75e18]650      if (p->code == charset) {
[55de792]651         msg_array = p->msg_array;
[db75e18]652         return old_charset;
653      }
654   }
655
656   /* nope, got to reparse message file */
657   parse_msg_file(charset_code);
658
659   /* add to list */
660   p = osnew(charset_li);
661   p->code = charset;
[55de792]662   p->msg_array = msg_array;
[db75e18]663   p->next = charset_head;
664   charset_head = p;
665
666   return old_charset;
667}
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