140 |
|
setambient(void) /* initialize calculation */ |
141 |
|
{ |
142 |
|
int readonly = 0; |
143 |
< |
long pos, flen; |
143 |
> |
long flen; |
144 |
|
AMBVAL amb; |
145 |
|
/* make sure we're fresh */ |
146 |
|
ambdone(); |
160 |
|
readonly = (ambfp = fopen(ambfile, "r")) != NULL; |
161 |
|
if (ambfp != NULL) { |
162 |
|
initambfile(0); /* file exists */ |
163 |
< |
pos = ftell(ambfp); |
163 |
> |
lastpos = ftell(ambfp); |
164 |
|
while (readambval(&amb, ambfp)) |
165 |
|
avinsert(avstore(&amb)); |
166 |
|
nambshare = nambvals; /* share loaded values */ |
174 |
|
return; /* avoid ambsync() */ |
175 |
|
} |
176 |
|
/* align file pointer */ |
177 |
< |
pos += (long)nambvals*AMBVALSIZ; |
177 |
> |
lastpos += (long)nambvals*AMBVALSIZ; |
178 |
|
flen = lseek(fileno(ambfp), (off_t)0, SEEK_END); |
179 |
< |
if (flen != pos) { |
179 |
> |
if (flen != lastpos) { |
180 |
|
sprintf(errmsg, |
181 |
|
"ignoring last %ld values in ambient file (corrupted)", |
182 |
< |
(flen - pos)/AMBVALSIZ); |
182 |
> |
(flen - lastpos)/AMBVALSIZ); |
183 |
|
error(WARNING, errmsg); |
184 |
< |
fseek(ambfp, pos, 0); |
184 |
> |
fseek(ambfp, lastpos, SEEK_SET); |
185 |
|
#ifndef _WIN32 /* XXX we need a replacement for that one */ |
186 |
< |
ftruncate(fileno(ambfp), (off_t)pos); |
186 |
> |
ftruncate(fileno(ambfp), (off_t)lastpos); |
187 |
|
#endif |
188 |
|
} |
189 |
|
} else if ((ambfp = fopen(ambfile, "w+")) != NULL) { |
190 |
|
initambfile(1); /* else create new file */ |
191 |
+ |
lastpos = ftell(ambfp); |
192 |
|
} else { |
193 |
|
sprintf(errmsg, "cannot open ambient file \"%s\"", ambfile); |
194 |
|
error(SYSTEM, errmsg); |
195 |
|
} |
196 |
< |
nunflshed++; /* lie */ |
196 |
< |
ambsync(); |
196 |
> |
ambsync(); /* load previous values */ |
197 |
|
} |
198 |
|
|
199 |
|
|
864 |
|
{ |
865 |
|
static struct flock fls; /* static so initialized to zeroes */ |
866 |
|
|
867 |
+ |
if (typ == fls.l_type) /* already called? */ |
868 |
+ |
return; |
869 |
|
fls.l_type = typ; |
870 |
|
if (fcntl(fileno(ambfp), F_SETLKW, &fls) < 0) |
871 |
|
error(SYSTEM, "cannot (un)lock ambient file"); |
879 |
|
AMBVAL avs; |
880 |
|
register int n; |
881 |
|
|
882 |
< |
if (nunflshed == 0) |
882 |
> |
if (ambfp == NULL) /* no ambient file? */ |
883 |
|
return(0); |
884 |
< |
if (lastpos < 0) /* initializing (locked in initambfile) */ |
885 |
< |
goto syncend; |
884 |
< |
/* gain exclusive access */ |
885 |
< |
aflock(F_WRLCK); |
884 |
> |
/* gain appropriate access */ |
885 |
> |
aflock(nunflshed ? F_WRLCK : F_RDLCK); |
886 |
|
/* see if file has grown */ |
887 |
|
if ((flen = lseek(fileno(ambfp), (off_t)0, SEEK_END)) < 0) |
888 |
|
goto seekerr; |
892 |
|
if (ambinp == NULL) |
893 |
|
error(SYSTEM, "fdopen failed in ambsync"); |
894 |
|
} |
895 |
< |
if (fseek(ambinp, lastpos, 0) < 0) |
895 |
> |
if (fseek(ambinp, lastpos, SEEK_SET) < 0) |
896 |
|
goto seekerr; |
897 |
|
while (n >= AMBVALSIZ) { /* load contributed values */ |
898 |
|
if (!readambval(&avs, ambinp)) { |
905 |
|
avinsert(avstore(&avs)); |
906 |
|
n -= AMBVALSIZ; |
907 |
|
} |
908 |
+ |
lastpos = flen - n; |
909 |
|
/*** seek always as safety measure |
910 |
|
if (n) ***/ /* alignment */ |
911 |
< |
if (lseek(fileno(ambfp), (off_t)(flen-n), SEEK_SET) < 0) |
911 |
> |
if (lseek(fileno(ambfp), (off_t)lastpos, SEEK_SET) < 0) |
912 |
|
goto seekerr; |
913 |
|
} |
914 |
|
#ifdef DEBUG |
919 |
|
error(CONSISTENCY, errmsg); |
920 |
|
} |
921 |
|
#endif |
921 |
– |
syncend: |
922 |
|
n = fflush(ambfp); /* calls write() at last */ |
923 |
< |
if ((lastpos = lseek(fileno(ambfp), (off_t)0, SEEK_CUR)) < 0) |
923 |
> |
if (n != EOF) |
924 |
> |
lastpos += (long)nunflshed*AMBVALSIZ; |
925 |
> |
else if ((lastpos = lseek(fileno(ambfp), (off_t)0, SEEK_CUR)) < 0) |
926 |
|
goto seekerr; |
927 |
+ |
|
928 |
|
aflock(F_UNLCK); /* release file */ |
929 |
|
nunflshed = 0; |
930 |
|
return(n); |
938 |
|
extern int |
939 |
|
ambsync(void) /* flush ambient file */ |
940 |
|
{ |
941 |
< |
if (nunflshed == 0) |
941 |
> |
if (ambfp == NULL) |
942 |
|
return(0); |
943 |
|
nunflshed = 0; |
944 |
|
return(fflush(ambfp)); |