fast access too lines in file

This commit is contained in:
Vitor Santos Costa 2016-09-21 14:47:05 -05:00
parent a478a83c27
commit 21324d7434

View File

@ -306,6 +306,29 @@ static Int file_size(USES_REGS1) {
return false;
}
static Int lines_in_file(USES_REGS1) {
Int sno = Yap_CheckStream(ARG1, (Input_Stream_f | Output_Stream_f),
"lines_in_file/2");
if (sno < 0)
return (FALSE);
if (GLOBAL_Stream[sno].status & Seekable_Stream_f &&
!(GLOBAL_Stream[sno].status &
(InMemory_Stream_f | Socket_Stream_f | Pipe_Stream_f))) {
FILE *f = GLOBAL_Stream[sno].file;
size_t count = 0;
int ch;
#if __ANDROID__
#define getw getc
#endif
while ((ch = getw(f)) >= 0) {
if (ch == '\n')
count++;
}
return Yap_unify(ARG3, MkIntegerTerm(count));
}
return false;
}
static Int access_file(USES_REGS1) {
Term tname = Deref(ARG1);
Term tmode = Deref(ARG2);
@ -618,6 +641,8 @@ void Yap_InitFiles(void) {
SafePredFlag);
Yap_InitCPred("same_file", 2, same_file, SafePredFlag | SyncPredFlag);
Yap_InitCPred("$access_file", 2, access_file, SafePredFlag | SyncPredFlag);
Yap_InitCPred("$lines_in_file", 2, lines_in_file,
SafePredFlag | SyncPredFlag);
Yap_InitCPred("access", 1, access_path, SafePredFlag | SyncPredFlag);
Yap_InitCPred("exists_directory", 1, exists_directory,
SafePredFlag | SyncPredFlag);