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yap-6.3/os/files.c
Vitor Santos Costa 530246688c jupyter
2018-02-25 00:29:08 +00:00

718 lines
19 KiB
C

/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: iopreds.c *
* Last rev: 5/2/88 *
* mods: *
* comments: Input/Output C implemented predicates *
* *
*************************************************************************/
#ifdef SCCS
static char SccsId[] = "%W% %G%";
#endif
/*
* This file includes the definition of a miscellania of standard predicates
* for yap refering to: Files and GLOBAL_Streams, Simple Input/Output,
*
*/
#include "sysbits.h"
#include "yapio.h"
#if _MSC_VER || defined(__MINGW32__)
#define SYSTEM_STAT _stat
#else
#define SYSTEM_STAT stat
#endif
const char *Yap_GetFileName(Term t USES_REGS) {
char *buf = Malloc(YAP_FILENAME_MAX + 1);
if (IsApplTerm(t) && FunctorOfTerm(t) == FunctorSlash) {
snprintf(buf, YAP_FILENAME_MAX, "%s/%s", Yap_GetFileName(ArgOfTerm(1, t)),
Yap_GetFileName(ArgOfTerm(1, t)));
}
return Yap_TextTermToText(t PASS_REGS);
}
/**
* @pred file_name_extension( ? BaseFile, ?Extension, ?FullNameO)
*
* Relate a file name with an extension. The extension is the filename's suffix
* and indicates the kind of the file.
*
* The predicate can be used to:
* - Given __FullName__, extract the extension as _Extension_, and the remainder
* as _BaseFile_. - Given _BaseFile_ and _?Extension_ obtain a _FullNameO_.
* ~~~~
* ~~~~
* Notice that:
* + if no suffix is found, file_name_extension/3 generates the empty
* suffu]kx, `''`. + the extension does not include the `,` separator; + the
* suffix may be longer thsn 3 characters + case should not matter in Windows
* and MacOS + paths may not correspond to valid file names.
*
* @return G
*/
static Int file_name_extension(USES_REGS1) {
Term t1;
Term t2;
Term t3 = Deref(ARG3);
int l = push_text_stack();
if (!IsVarTerm(t3)) {
// full path is given.
const char *f = Yap_GetFileName(t3);
const char *ext;
char *base;
bool rc = true;
seq_type_t typ = Yap_TextType(t3);
if (!f) {
pop_text_stack(l);
return false;
}
size_t len_b = strlen(f), lenb_b;
char *candidate = strrchr(f, '.');
char *file = strrchr(f, '/');
if (candidate && file && candidate > file) {
lenb_b = candidate - f;
ext = candidate + 1;
} else {
lenb_b = len_b;
ext = "";
}
base = Malloc(lenb_b + 1);
memcpy(base, f, lenb_b);
base[lenb_b] = '\0';
if (IsVarTerm(t1 = Deref(ARG1))) {
// should always succeed
rc = Yap_unify(t1, Yap_MkTextTerm(base, typ));
} else {
char *f_a = (char *)Yap_GetFileName(t1 PASS_REGS);
#if __APPLE__ || _WIN32
rc = strcasecmp(f_a, base) == 0;
#else
rc = strcmp(f_a, base) == 0;
#endif
}
if (rc) {
if (IsVarTerm(t2 = Deref(ARG2))) {
// should always succeed
rc = Yap_unify(t2, Yap_MkTextTerm(ext, typ));
} else {
char *f_a = (char *)Yap_TextTermToText(t2 PASS_REGS);
if (f_a[0] == '.') {
f_a += 1;
}
#if __APPLE__ || _WIN32
rc = strcasecmp(f_a, ext) == 0;
#else
rc = strcmp(f_a, ext) == 0;
#endif
}
}
pop_text_stack(l);
return rc;
} else {
const char *f;
char *f2;
seq_type_t typ, typ1 = Yap_TextType((t1 = Deref(ARG1))),
typ2 = Yap_TextType((t2 = Deref(ARG2)));
if (typ1 == typ2) {
typ = typ1;
} else if (typ1 == YAP_STRING_ATOM || typ2 == YAP_STRING_ATOM) {
typ = YAP_STRING_ATOM;
} else {
typ = YAP_STRING_STRING;
}
if (!(f = Yap_TextTermToText(t1 PASS_REGS))) {
pop_text_stack(l);
return false;
}
if (!(f2 = (char *)Yap_TextTermToText(t2 PASS_REGS))) {
pop_text_stack(l);
return false;
}
if (f2[0] == '.') {
f2++;
}
size_t lenb_b = strlen(f);
char *o = Realloc((void *)f, lenb_b + strlen(f2) + 2);
o[lenb_b] = '.';
o += lenb_b + 1;
pop_text_stack(l);
return strcpy(o, f2) && (t3 = Yap_MkTextTerm(o, typ)) &&
Yap_unify(t3, ARG3);
}
}
static Int access_path(USES_REGS1) {
Term tname = Deref(ARG1);
if (IsVarTerm(tname)) {
Yap_Error(INSTANTIATION_ERROR, tname, "access");
return false;
} else if (!IsAtomTerm(tname)) {
Yap_Error(TYPE_ERROR_ATOM, tname, "access");
return false;
} else {
VFS_t *vfs;
char *s = RepAtom(AtomOfTerm(tname))->StrOfAE;
if (!s) return false;
if ((vfs = vfs_owner(s))) {
vfs_stat st;
bool rc = vfs->stat(vfs, s, &st);
UNLOCK(GLOBAL_Stream[sno].streamlock);
return rc;
}
#if HAVE_STAT
struct SYSTEM_STAT ss;
char *file_name;
file_name = RepAtom(AtomOfTerm(tname))->StrOfAE;
if (SYSTEM_STAT(file_name, &ss) != 0) {
/* ignore errors while checking a file */
return true;
}
return true;
#else
return false;
#endif
}
}
static Int exists_file(USES_REGS1) {
Term tname = Deref(ARG1);
char *file_name;
if (IsVarTerm(tname)) {
Yap_Error(INSTANTIATION_ERROR, tname, "access");
return FALSE;
} else if (!IsAtomTerm(tname)) {
Yap_Error(TYPE_ERROR_ATOM, tname, "access");
return FALSE;
} else {
VFS_t *vfs;
char *s = RepAtom(AtomOfTerm(tname))->StrOfAE;
if (!s) return false;
if ((vfs = vfs_owner(s))) {
vfs_stat st;
bool rc = vfs->stat(vfs, s, &st);
UNLOCK(GLOBAL_Stream[sno].streamlock);
return rc;
}
#if HAVE_STAT
struct SYSTEM_STAT ss;
file_name = RepAtom(AtomOfTerm(tname))->StrOfAE;
if (SYSTEM_STAT(file_name, &ss) != 0) {
/* ignore errors while checking a file */
return FALSE;
}
#if _MSC_VER
return ss.st_mode & S_IFREG;
#else
return S_ISREG(ss.st_mode);
#endif
#else
return FALSE;
#endif
}
}
static Int file_exists(USES_REGS1) {
Term tname = Deref(ARG1);
char *file_name;
if (IsVarTerm(tname)) {
Yap_Error(INSTANTIATION_ERROR, tname, "access");
return FALSE;
} else if (!IsAtomTerm(tname)) {
Yap_Error(TYPE_ERROR_ATOM, tname, "access");
return FALSE;
} else {
#if HAVE_STAT
struct SYSTEM_STAT ss;
file_name = RepAtom(AtomOfTerm(tname))->StrOfAE;
if (SYSTEM_STAT(file_name, &ss) != 0) {
if (errno == ENOENT)
return false;
PlIOError(SYSTEM_ERROR_OPERATING_SYSTEM, tname, "error %s",
strerror(errno));
return false;
}
return true;
#else
return FALSE;
#endif
}
}
static Int time_file(USES_REGS1) {
Term tname = Deref(ARG1);
if (IsVarTerm(tname)) {
Yap_Error(INSTANTIATION_ERROR, tname, "access");
return FALSE;
} else if (!IsAtomTerm(tname)) {
Yap_Error(TYPE_ERROR_ATOM, tname, "access");
return FALSE;
} else {
const char *n = RepAtom(AtomOfTerm(tname))->StrOfAE;
VFS_t *vfs;
if ((vfs = vfs_owner(n))) {
vfs_stat s;
vfs->stat(vfs, n, &s);
return Yap_unify(ARG2, MkIntegerTerm(s.st_mtimespec.tv_sec));
}
#if __WIN32
FILETIME ft;
HANDLE hdl;
Term rc;
if ((hdl = CreateFile(n, 0, 0, NULL, OPEN_EXISTING, 0, 0)) == 0) {
Yap_WinError("in time_file");
return false;
}
if (GetFileTime(hdl, NULL, NULL, &ft) == 0) {
Yap_WinError("in time_file");
return false;
}
// Convert the last-write time to local time.
// FileTimeToSystemTime(&ftWrite, &stUTC);
// SystemTimeToTzSpecificLocalTime(NULL, &stUTC, &stLocal);
CloseHandle(hdl);
ULONGLONG qwResult;
// Copy the time into a quadword.
qwResult = (((ULONGLONG)ft.dwHighDateTime) << 32) + ft.dwLowDateTime;
#if SIZEOF_INT_P == 8
rc = MkIntegerTerm(qwResult);
#elif USE_GMP
char s[64];
MP_INT rop;
snprintf(s, 64, "%I64d", (long long int)n);
mpz_init_set_str(&rop, s, 10);
rc = Yap_MkBigIntTerm((void *)&rop PASS_REGS);
#else
rc = MkIntegerTerm(ft.dwHighDateTime);
#endif
return Yap_unify(ARG2, rc);
#elif HAVE_STAT
struct SYSTEM_STAT ss;
if (SYSTEM_STAT(n, &ss) != 0) {
/* ignore errors while checking a file */
return FALSE;
}
return Yap_unify(ARG2, MkIntegerTerm(ss.st_mtime));
#else
return FALSE;
#endif
}
}
static Int file_size(USES_REGS1) {
int rc;
Int sno = Yap_CheckStream(
ARG1, (Input_Stream_f | Output_Stream_f | Socket_Stream_f),
"file_size/2");
if (sno < 0)
return (FALSE);
VFS_t *vfs;
char *s = RepAtom(GLOBAL_Stream[sno].name)->StrOfAE;
if (!s) return false;
if ((vfs = vfs_owner(s))) {
vfs_stat st;
vfs->stat(vfs, s, &st);
UNLOCK(GLOBAL_Stream[sno].streamlock);
return Yap_unify_constant(ARG2, MkIntegerTerm(st.st_size));
}
if (GLOBAL_Stream[sno].status & Seekable_Stream_f &&
!(GLOBAL_Stream[sno].status &
(InMemory_Stream_f | Socket_Stream_f | Pipe_Stream_f))) {
// there
struct stat file_stat;
if ((rc = fstat(fileno(GLOBAL_Stream[sno].file), &file_stat)) < 0) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
if (rc == ENOENT)
PlIOError(EXISTENCE_ERROR_SOURCE_SINK, ARG1, "%s in file_size",
strerror(errno));
else
PlIOError(PERMISSION_ERROR_INPUT_STREAM, ARG1, "%s in file_size",
strerror(errno));
return false;
}
// and back again
UNLOCK(GLOBAL_Stream[sno].streamlock);
return Yap_unify_constant(ARG2, MkIntegerTerm(file_stat.st_size));
}
UNLOCK(GLOBAL_Stream[sno].streamlock);
return false;
}
static Int lines_in_file(USES_REGS1) {
Int sno = Yap_CheckStream(ARG1, (Input_Stream_f), "lines_in_file/2");
if (sno < 0)
return false;
FILE *f = GLOBAL_Stream[sno].file;
size_t count = 0;
int ch;
#if __ANDROID__
#define getw getc
#endif
if (!f)
return false;
while ((ch = getw(f)) >= 0) {
if (ch == '\n') {
count++;
}
}
return Yap_unify(ARG2, MkIntegerTerm(count));
}
static Int access_file(USES_REGS1) {
Term tname = Deref(ARG1);
Term tmode = Deref(ARG2);
char *ares;
Atom atmode;
if (IsVarTerm(tmode)) {
Yap_Error(INSTANTIATION_ERROR, tmode, "access_file/2");
return FALSE;
} else if (!IsAtomTerm(tmode)) {
Yap_Error(TYPE_ERROR_ATOM, tname, "access_file/2");
return FALSE;
}
atmode = AtomOfTerm(tmode);
if (IsVarTerm(tname)) {
Yap_Error(INSTANTIATION_ERROR, tname, "access_file/2");
return FALSE;
} else if (!IsAtomTerm(tname)) {
Yap_Error(TYPE_ERROR_ATOM, tname, "access_file/2");
return FALSE;
} else {
if (atmode == AtomNone)
return TRUE;
if (!(ares = RepAtom(AtomOfTerm(tname))->StrOfAE))
return FALSE;
}
VFS_t *vfs;
if ((vfs = vfs_owner(ares))) {
vfs_stat o;
if (vfs->stat(vfs, ares, &o)) {
if (atmode == AtomExist)
return true;
else if (atmode == AtomExists)
return true;
else if (atmode == AtomWrite)
return o.st_mode & VFS_CAN_WRITE;
else if (atmode == AtomRead)
return o.st_mode & VFS_CAN_READ;
else if (atmode == AtomAppend)
return o.st_mode & VFS_CAN_WRITE;
else if (atmode == AtomCsult)
return o.st_mode & VFS_CAN_READ;
else if (atmode == AtomExecute)
return o.st_mode & VFS_CAN_EXEC;
else {
Yap_Error(DOMAIN_ERROR_IO_MODE, tmode, "access_file/2");
return FALSE;
}
} else {
return false;
}
}
#if HAVE_ACCESS
#if _WIN32
{
int mode;
if (atmode == AtomExist)
mode = 00;
else if (atmode == AtomExists)
mode = 00;
else if (atmode == AtomWrite)
mode = 02;
else if (atmode == AtomRead)
mode = 04;
else if (atmode == AtomAppend)
mode = 03;
else if (atmode == AtomCsult)
mode = 04;
else if (atmode == AtomExecute)
mode = 00; // can always execute?
else {
Yap_Error(DOMAIN_ERROR_IO_MODE, tmode, "access_file/2");
return FALSE;
}
if (access(ares, mode) < 0) {
/* ignore errors while checking a file */
return false;
}
return true;
}
#else
{
int mode;
if (atmode == AtomExist)
mode = F_OK;
else if (atmode == AtomExists)
mode = F_OK;
else if (atmode == AtomWrite)
mode = W_OK;
else if (atmode == AtomRead)
mode = R_OK;
else if (atmode == AtomAppend)
mode = W_OK;
else if (atmode == AtomCsult)
mode = R_OK;
else if (atmode == AtomExecute)
mode = X_OK;
else {
Yap_Error(DOMAIN_ERROR_IO_MODE, tmode, "access_file/2");
return FALSE;
}
if (access(ares, mode) < 0) {
/* ignore errors while checking a file */
return false;
}
return true;
}
#endif
#elif HAVE_STAT
{
struct SYSTEM_STAT ss;
if (SYSTEM_STAT(ares, &ss) != 0) {
/* ignore errors while checking a file */
return FALSE;
}
return TRUE;
}
#else
return FALSE;
#endif
}
static Int exists_directory(USES_REGS1) {
Term tname = Deref(ARG1);
char *file_name;
if (IsVarTerm(tname)) {
Yap_Error(INSTANTIATION_ERROR, tname, "exists_directory/1");
return FALSE;
} else if (!IsAtomTerm(tname)) {
Yap_Error(TYPE_ERROR_ATOM, tname, "exists_directory/1");
return FALSE;
} else {
VFS_t *vfs;
char *s = Yap_VF(RepAtom(AtomOfTerm(tname))->StrOfAE);
if (!s) return false;
if ((vfs = vfs_owner(s))) {
bool rc = true;
return vfs->isdir(vfs, s);
UNLOCK(GLOBAL_Stream[sno].streamlock);
return rc;
}
#if HAVE_STAT
struct SYSTEM_STAT ss;
file_name = Yap_VF(RepAtom(AtomOfTerm(tname))->StrOfAE);
if (SYSTEM_STAT(file_name, &ss) != 0) {
/* ignore errors while checking a file */
return false;
}
return (S_ISDIR(ss.st_mode));
#else
return FALSE;
#endif
}
}
static Int is_absolute_file_name(USES_REGS1) { /* file_base_name(Stream,N) */
Term t = Deref(ARG1);
Atom at;
bool rc;
if (IsVarTerm(t)) {
Yap_Error(INSTANTIATION_ERROR, t, "file_base_name/2");
return false;
}
int l = push_text_stack();
const char *buf = Yap_TextTermToText(t PASS_REGS);
if (buf) {
rc = Yap_IsAbsolutePath(buf, true);
} else {
at = AtomOfTerm(t);
#if _WIN32
rc = PathIsRelative(RepAtom(at)->StrOfAE);
#else
rc = RepAtom(at)->StrOfAE[0] == '/';
#endif
}
pop_text_stack(l);
return rc;
}
static Int file_base_name(USES_REGS1) { /* file_base_name(Stream,N) */
Term t = Deref(ARG1);
Atom at;
if (IsVarTerm(t)) {
Yap_Error(INSTANTIATION_ERROR, t, "file_base_name/2");
return FALSE;
}
at = AtomOfTerm(t);
const char *c = RepAtom(at)->StrOfAE;
const char *s;
#if HAVE_BASENAME && 0 // DISABLED: Linux basename is not compatible with
// file_base_name in SWI and GNU
char c1[YAP_FILENAME_MAX + 1];
strncpy(c1, c, YAP_FILENAME_MAX);
s = basename(c1);
#else
Int i = strlen(c);
while (i && !Yap_dir_separator((int)c[--i]))
;
if (Yap_dir_separator((int)c[i])) {
i++;
}
s = c + i;
#endif
return Yap_unify(ARG2, MkAtomTerm(Yap_LookupAtom(s)));
}
static Int file_directory_name(USES_REGS1) { /* file_directory_name(Stream,N) */
Term t = Deref(ARG1);
Atom at;
if (IsVarTerm(t)) {
Yap_Error(INSTANTIATION_ERROR, t, "file_directory_name/2");
return false;
}
at = AtomOfTerm(t);
const char *c = RepAtom(at)->StrOfAE;
#if HAVE_BASENAME && 0 // DISABLED: Linux basename is not compatible with
// file_base_name in SWI and GNU
const char *s;
char c1[YAP_FILENAME_MAX + 1];
strncpy(c1, c, YAP_FILENAME_MAX);
s = dirname(c1);
#else
char s[YAP_FILENAME_MAX + 1];
Int i = strlen(c);
strncpy(s, c, YAP_FILENAME_MAX);
while (--i) {
if (Yap_dir_separator((int)c[i]))
break;
}
if (i == 0) {
s[0] = '.';
i = 1;
}
s[i] = '\0';
#endif
return Yap_unify(ARG2, MkAtomTerm(Yap_LookupAtom(s)));
}
static Int same_file(USES_REGS1) {
char *f1 = RepAtom(AtomOfTerm(Deref(ARG1)))->StrOfAE;
char *f2 = RepAtom(AtomOfTerm(Deref(ARG2)))->StrOfAE;
if (strcmp(f1, f2) == 0)
return TRUE;
#if HAVE_LSTAT
{
int out;
struct stat *b1, *b2;
while ((char *)HR + sizeof(struct stat) * 2 > (char *)(ASP - 1024)) {
if (!Yap_gcl(2 * sizeof(struct stat), 2, ENV, Yap_gcP())) {
Yap_Error(RESOURCE_ERROR_STACK, TermNil, LOCAL_ErrorMessage);
return FALSE;
}
}
b1 = (struct stat *)HR;
b2 = b1 + 1;
if (strcmp(f1, "user_input") == 0) {
if (fstat(fileno(GLOBAL_Stream[0].file), b1) == -1) {
/* file does not exist, but was opened? Return -1 */
return FALSE;
}
} else if (strcmp(f1, "user_output") == 0) {
if (fstat(fileno(GLOBAL_Stream[1].file), b1) == -1) {
/* file does not exist, but was opened? Return -1 */
return FALSE;
}
} else if (strcmp(f1, "user_error") == 0) {
if (fstat(fileno(GLOBAL_Stream[2].file), b1) == -1) {
/* file does not exist, but was opened? Return -1 */
return FALSE;
}
} else if (stat(f1, b1) == -1) {
/* file does not exist, but was opened? Return -1 */
return FALSE;
}
if (strcmp(f2, "user_input") == 0) {
if (fstat(fileno(GLOBAL_Stream[0].file), b2) == -1) {
/* file does not exist, but was opened? Return -1 */
return FALSE;
}
} else if (strcmp(f2, "user_output") == 0) {
if (fstat(fileno(GLOBAL_Stream[1].file), b2) == -1) {
/* file does not exist, but was opened? Return -1 */
return FALSE;
}
} else if (strcmp(f2, "user_error") == 0) {
if (fstat(fileno(GLOBAL_Stream[2].file), b2) == -1) {
/* file does not exist, but was opened? Return -1 */
return FALSE;
}
} else if (stat(f2, b2) == -1) {
/* file does not exist, but was opened? Return -1 */
return FALSE;
}
out = (b1->st_ino == b2->st_ino
#ifdef __LCC__
&& memcmp((const void *)&(b1->st_dev), (const void *)&(b2->st_dev),
sizeof(buf1.st_dev)) == 0
#else
&& b1->st_dev == b2->st_dev
#endif
);
return out;
}
#else
return (FALSE);
#endif
}
void Yap_InitFiles(void) {
Yap_InitCPred("file_base_name", 2, file_base_name, SafePredFlag);
Yap_InitCPred("file_directory_name", 2, file_directory_name, SafePredFlag);
Yap_InitCPred("is_absolute_file_name", 1, is_absolute_file_name,
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);
Yap_InitCPred("exists_file", 1, exists_file, SafePredFlag | SyncPredFlag);
Yap_InitCPred("$file_exists", 1, file_exists, SafePredFlag | SyncPredFlag);
Yap_InitCPred("time_file64", 2, time_file, SafePredFlag | SyncPredFlag);
Yap_InitCPred("time_file", 2, time_file, SafePredFlag | SyncPredFlag);
Yap_InitCPred("file_size", 2, file_size, SafePredFlag | SyncPredFlag);
Yap_InitCPred("file_name_extension", 3, file_name_extension,
SafePredFlag | SyncPredFlag);
}