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C/C++ Source or Header | 1996-01-24 | 31.4 KB | 853 lines

/* Copyright (C) 1996 DJ Delorie, see COPYING.DJ for details */ /* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */ /* This is file FSTAT.C */ /* * Almost a 100% U**X-compatible fstat() substitute. * * Usage: * * That's easy: just put this in libc.a, and then call fstat() as usual. * * Rationale: * * Many Unix-born programs make heavy use of fstat() library * function to make decisions on files' equality, size, access * attributes etc. In the MS-DOS environment, many implementations * of fstat() are crippled, because DOS makes it very hard to get to * certain pieces of information about files and directories. Thus * porting a program to DOS is usually an exercise in #ifdef'ing. * This implementation facilitates porting Unix programs to MS-DOS * by providing an fstat() which is much more Unix-compatible than * those of most DOS-based C compilers (e.g., Borland's). * Specifically, the following issues are taken care of: * * 1. Mode bits are returned for the actual file, files are NOT * reported read-only (as in Borland's library fstat()). * 2. Mode bits are set for all 3 groups (user, group, other). * 3. Device code (st_dev, st_rdev) is correctly reported (0 = 'A', * 1 = 'B' etc.). * 4. Character device names (such as /dev/con, lpt1, aux etc.) are * treated as if they were on a special drive called `@:' * (st_dev = -1). The "character special" mode bit is set * for these devices. * 5. The inode number (st_ino) is taken from the starting cluster * number of the file. If the cluster number is unavailable, it * is invented using the file's name in a manner that minimizes * the possibility of inventing an inode which already belongs * to another file. See below for details. * 6. Executable files are found based on files' extensions and * magic numbers present at their beginning, and their execute * bits are set. * * Lossage: * * Beautiful as the above sounds, this implementation does fail * under certain circumstances. The following is a list of known * problems: * * 1. Files open on networked drives mounted by Novell Netware * before revision 4.x cannot be traced using DOS System File * Table. Therefore, name, extension, file attributes and the * drive letter are not available for these. Until somebody * tells me how this information can be obtained under Novell, * nothing could be done here. For the time being, these files * will get st_dev of -2. * 2. For files which reside on networked drives, the inode number * is always invented, because network redirectors usually do * not bring that info with them. * 3. Empty files do not have a starting cluster number, because * DOS doesn't allocate one until you actually write something * to a file. For these the inode is also invented. * 4. If the st_ino field is a 16 bit number, the invented inode * numbers are from 65535 and down, assuming that most disks have * unised portions near their end. Valid cluster numbers are 16-bit * unisgned integers, so a possibility of a clash exists, although * the last 80 or more cluster numbers are unused on all drives * I've seen. If the st_ino is 32 bit, then invented inodes are * all greater than 64k, which totally eliminates a possibility * of a clash with an actual cluster number. * 5. As this implementation relies heavily on undocumented DOS * features, it will fail to get actual file info in environments * other than native DOS, such as DR-DOS, OS/2 etc. For these, * the function will return whatever info is available with * conventional DOS calls, which is no less than any other * implementation could do. This fstat() might also fail for * future DOS versions, if the layout of DOS System File Table * is changed; however, this seems unlikely. * * Copyright (c) 1994-1996 Eli Zaretskii <eliz@is.elta.co.il> * * This software may be used freely so long as this copyright notice is * left intact. There is no warranty on this software. * */ /* * Tested with DJGPP port of GNU C compiler, versions 1.11maint5 and 1.12m2, * under MS-DOS 3.3, 4.01, 5.0, 6.20 (with and without DoubleSpace) and * with networked drives under XFS 1.76, Novell Netware 3.22, and * TSoft NFS 0.24Beta. * */ #include <libc/stubs.h> #include <string.h> #include <stdlib.h> #include <stdio.h> #include <errno.h> #include <time.h> #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <dpmi.h> #include <go32.h> #include <libc/farptrgs.h> #include <libc/bss.h> #include "xstat.h" #define _STAT_INODE 1 /* should we bother getting inode numbers? */ #define _STAT_EXEC_EXT 2 /* get execute bits from file extension? */ #define _STAT_EXEC_MAGIC 4 /* get execute bits from magic signature? */ #define _STAT_DIRSIZE 8 /* compute directory size? */ #define _STAT_ROOT_TIME 0x10 /* try to get root dir time stamp? */ #define _STAT_WRITEBIT 0x20 /* fstat() needs write bit? */ /* Should we bother about executables at all? */ #define _STAT_EXECBIT (_STAT_EXEC_EXT | _STAT_EXEC_MAGIC) /* Should we bother about any access bits? */ #define _STAT_ACCESS (_STAT_WRITEBIT | _STAT_EXECBIT) /* Do we need SFT info at all? */ #define _STAT_NEEDS_SFT (_STAT_WRITEBIT | _STAT_EXEC_EXT | _STAT_INODE) /* * Lower-level assist functions to get a starting cluster of a file, * which will serve as an inode number. The starting cluster is * found in the System File Table entry (an internal structure of * DOS) which belongs to our file. * * Much of the following code is derived from file H2NAME.C, which * came with ``Undocumented DOS'', 1st edition. */ /* Selectors for conventional memory and our program's memory. */ static unsigned short dos_mem_base, our_mem_base; /* Array of SFT entry sizes as function of DOS version. */ static size_t sft_size_list[] = {0, 0x28, 0x35, 0x3b}; /* Actual size of SFT entry for the version of DOS under which we are running. */ static size_t sft_size; /* Static array to hold a copy of SFT entry. Should be at least as long as the largest number in sft_size_list[]. */ static unsigned char sft_buf[0x40]; /* Linear address of pointer to Job File Table (JFT) which is an array of indices into the SFT which correspond to open file handles. */ static unsigned long htbl_ptr_addr; /* True version of DOS (not the one simulated by SETVER). */ static unsigned short dos_major, dos_minor; /* Segment and offset of first SFT sub-table. All searches start from this address. */ static unsigned short sft_start_seg, sft_start_off; /* This holds the failure bits from last call to fstat_init(), so we can return them each time fstat_assist() is called. */ static unsigned short fstat_init_bits; /* Holds the last seen value of __bss_count, to be safe for restarted programs (emacs). */ static int fstat_count = -1; /* Initialization routine, called once per program run. * Finds DOS version, SFT entry size and addresses of * program handle table and first SFT sub-table. */ static int fstat_init(void) { __dpmi_regs regs; int sft_ptr_addr; unsigned short true_dos_version; /* Selectors for _farXXX() functions. */ dos_mem_base = _dos_ds; our_mem_base = _my_ds(); /* Each DOS program has a table of file handles which are used by * DOS open() call. This table holds, for each handle which is in * use, the index into the System File Tables' list which contains * data about this handle. The pointer to that handle table is found * at offset 34h in the program's PSP. */ /* Linear address of pointer to the handle table. We postpone * dereferencing this pointer to obtain the address of the handle * table until we're actually called for a specific handle, because * somebody could in the meanwhile change that address, e.g. by * calling INT 21h/AX=67h to enlarge the maximum number of file * handles. */ htbl_ptr_addr = (_go32_info_block.linear_address_of_original_psp & 0xfffff) + 0x34; /* * Find the pointer to the first subtable in the list of SFT's. * It is stored at offset 4 in the DOS List-of-Lists area, a ptr * to which is returned by the undocumented DOS function 52h. * We don't check FLAGS after 52h returns because Ralph Brown's * Interrupt List doesn't say FLAGS are set to indicate a * failure. */ regs.h.ah = 0x52; __dpmi_int(0x21, ®s); /* Linear addres of pointer to SFT list. */ sft_ptr_addr = MK_FOFF(regs.x.es, regs.x.bx + 4); /* SFT entry size depends on DOS version. We need exact knowledge about DOS internals, so we need the TRUE DOS version (not the simulated one by SETVER), if that's available. */ true_dos_version = _get_dos_version(1); dos_major = true_dos_version >> 8; dos_minor = true_dos_version & 0xff; sft_size = sft_size_list[dos_major > 4 ? 3 : dos_major - 1]; if (!sft_size) /* unsupported DOS version */ { _djstat_fail_bits |= _STFAIL_OSVER; return 0; } /* Segment and offset of start of SFT list. */ sft_start_off = _farpeekw(dos_mem_base, sft_ptr_addr); sft_start_seg = _farpeekw(dos_mem_base, sft_ptr_addr + 2); return 1; } /* Given a handle, copy contents of System File Table entry which * belongs to that handle into a local buffer, and return the index * into the SFT array where our entry was found. In case of failure * to use SFT, return -2. If FHANDLE is illegal, return -1. */ static short get_sft_entry(int fhandle) { unsigned long sft_seg; unsigned short sft_off; unsigned long htbl_addr; short sft_idx, retval; _djstat_fail_bits = fstat_init_bits; /* Force initialization if we were restarted (emacs). */ if (fstat_count != __bss_count) { fstat_count = __bss_count; dos_major = 0; } /* If first time called, initialize. */ if (!dos_major && !fstat_init()) { fstat_init_bits = _djstat_fail_bits; return -2; } /* Test file handle for validity. * For DOS 3.x and later, the number of possible file handles * is at offset 32h in the PSP; for prior versions, it is 20. */ if (fhandle < 0 || fhandle >= (_osmajor < 3 ? 20 : _farpeekw(dos_mem_base, (_go32_info_block.linear_address_of_original_psp & 0xfffff) + 0x32))) return -1; /* Linear address of the handle table. */ htbl_addr = MK_FOFF(_farpeekw(dos_mem_base, htbl_ptr_addr + 2), _farpeekw(dos_mem_base, htbl_ptr_addr)); /* Index of the entry for our file handle in the SFT array. */ retval = sft_idx = _farpeekb(dos_mem_base, htbl_addr + fhandle); if (sft_idx < 0) /* invalid file handle or bad handle table */ { _djstat_fail_bits |= _STFAIL_SFTIDX; return -1; } /* Given the index into the SFT list, find our SFT entry. * The list consists of arrays (sub-tables) of entries, each sub- * table preceeded by a header. The header holds a pointer to the * next sub-table in the list and number of entries in this sub-table. * The list is searched until the sub-table which contains our * target is found, then the sub-table entries are skipped until * we arrive at our target. */ /* Segment (shifted 4 bits left) and offset of start of SFT list. */ sft_off = sft_start_off; sft_seg = MK_FOFF(sft_start_seg, 0); while (sft_off != 0xFFFF) { unsigned long entry_addr = sft_seg + sft_off; short subtable_len = _farpeekw(dos_mem_base, entry_addr + 4); if (sft_idx < subtable_len) { /* Our target is in this sub-table. Pull in the entire * SFT entry for use by fstat_assist(). */ movedata(dos_mem_base, (entry_addr + 6 + sft_idx * sft_size) & 0x000fffff, our_mem_base, (unsigned int)sft_buf, sft_size); return retval; } /* Our target not in this subtable. * Subtract the number of entries in this sub-table from the * index of our entry, and proceed to next sub-table. */ sft_idx -= subtable_len; sft_off = _farpeekw(dos_mem_base, entry_addr); sft_seg = MK_FOFF(_farpeekw(dos_mem_base, entry_addr + 2), 0); } /* Get here only by error, which probably means unsupported DOS version. */ _djstat_fail_bits |= _STFAIL_SFTNF; return -2; } /* fstat_assist() is where all the actual work is done. * It uses SFT entry, if available and its contents are verified. * Otherwise, it finds all the available info by conventional * DOS calls. */ static int fstat_assist(int fhandle, struct stat *stat_buf) { short have_trusted_values = 1; unsigned int dos_ftime; char drv_no; unsigned char is_dev; unsigned char is_remote; short sft_idx = -1; unsigned short sft_fdate, sft_ftime; long sft_fsize; unsigned short trusted_ftime = 0, trusted_fdate = 0; long trusted_fsize = 0; _djstat_fail_bits = 0; /* Get pointer to an SFT entry which holds data for our handle. */ if ( (_djstat_flags & _STAT_NEEDS_SFT) == 0 && (sft_idx = get_sft_entry(fhandle)) == -1) { errno = EBADF; return -1; } /* Initialize buffers. */ memset(stat_buf, 0, sizeof(struct stat)); dos_ftime = 0; /* Get some info about this handle by conventional DOS calls. These * will serve as verification of SFT entry contents and also as * fall-back in case SFT method fails. */ if (_getftime(fhandle, &dos_ftime) == 0 && (trusted_fsize = __filelength(fhandle)) != -1L) { trusted_ftime = dos_ftime & 0xffff; trusted_fdate = dos_ftime >> 16; } else have_trusted_values = 0; /* First, fill the fields which are constant under DOS. */ stat_buf->st_uid = getuid(); stat_buf->st_gid = getgid(); stat_buf->st_nlink = 1; #ifndef NO_ST_BLKSIZE stat_buf->st_blksize = _go32_info_block.size_of_transfer_buffer; #endif /* If SFT entry for our handle is required and available, we will use it. */ if ( (_djstat_flags & _STAT_NEEDS_SFT) == 0 && sft_idx >= 0) { /* Determine positions of data items in the SFT. */ size_t fattr_ofs, name_ofs, ext_ofs, fsize_ofs, fdate_ofs, ftime_ofs, clust_ofs; switch (dos_major) { case 2: fattr_ofs = 2; drv_no = sft_buf[3] - 1; /* 1 = 'A' etc. */ is_dev = drv_no < 0; /* sft_buf[3] = 0 */ name_ofs = 4; ext_ofs = 0x0b; fsize_ofs = 0x13; fdate_ofs = 0x17; ftime_ofs = 0x19; clust_ofs = 0x1c; is_remote = 0; /* DOS 2.x didn't have remote files */ break; case 3: fattr_ofs = 4; drv_no = sft_buf[5] & 0x3f; is_dev = sft_buf[5] & 0x80; is_remote = sft_buf[6] & 0x80; if (dos_minor == 0) { name_ofs = 0x21; ext_ofs = 0x29; } else /* DOS 3.1 - 3.3x */ { name_ofs = 0x20; ext_ofs = 0x28; } clust_ofs = 0x0b; ftime_ofs = 0x0d; fdate_ofs = 0x0f; fsize_ofs = 0x11; break; default: /* DOS 4 and up */ fattr_ofs = 4; drv_no = sft_buf[5] & 0x3f; is_dev = sft_buf[5] & 0x80; is_remote = sft_buf[6] & 0x80; clust_ofs = 0x0b; ftime_ofs = 0x0d; fdate_ofs = 0x0f; fsize_ofs = 0x11; name_ofs = 0x20; ext_ofs = 0x28; } if (is_dev) { /* We have a character device. * We will pretend as if they all reside on a special * drive `@:', which is illegal in DOS, and just happens * to give a neat st_dev (= '@' - 'A') = -1. */ stat_buf->st_dev = -1; #ifdef HAVE_ST_RDEV stat_buf->st_rdev = -1; #endif if ( (_djstat_flags & _STAT_INODE) == 0 ) { /* Character device names are all at most 8-character long. */ short i = 8; char *src = sft_buf + name_ofs; char dev_name[16], *dst = dev_name + 7; strcpy(dev_name, "@:\\dev\\ "); /* pad with 8 blanks */ while (i-- && *src != ' ') /* copy non-blank chars */ *dst++ = *src++; stat_buf->st_ino = _invent_inode(dev_name, 0, 0); } /* Should we make printer devices write-only here? */ stat_buf->st_mode |= (S_IFCHR | READ_ACCESS | WRITE_ACCESS); /* We will arrange things so that devices have current time in * the access-time and modified-time fields of struct stat. */ stat_buf->st_atime = stat_buf->st_mtime = time(0); /* MS-DOS returns the time of boot when _getftime() is called * for character devices, but this is undocumented and * unsupported by DOS clones (e.g. DR-DOS). It is also * inconsistent with our stat(). Therefore, we will arrange * things so that devices have zero (the beginning of times) * in creation-time field. */ dos_ftime = 0; stat_buf->st_ctime = _file_time_stamp(dos_ftime); return 0; } /* Files are not allowed to fail DOS calls for their time * stamps and size. */ else if (have_trusted_values) { /* This is a regular, existing file. It cannot be a * directory, because DOS won't let us open() a directory. * Each file under MS-DOS is always readable by everyone. */ stat_buf->st_mode |= (S_IFREG | READ_ACCESS); /* We will be extra careful in trusting SFT data: it must be * consistent with date, time and size of the file as known * from conventional DOS calls. */ sft_fdate = *((unsigned short *)(sft_buf + fdate_ofs)); sft_ftime = *((unsigned short *)(sft_buf + ftime_ofs)); sft_fsize = *((long *)(sft_buf + fsize_ofs)); if (sft_ftime == trusted_ftime && sft_fdate == trusted_fdate && sft_fsize == trusted_fsize) { /* Now we are ready to get the SFT info. */ char sft_extension[4], *dst = sft_extension + 2; unsigned char *src = sft_buf + ext_ofs + 2; int i = 3; /* Get the file's extension. It is held in the SFT entry * as a blank-padded 3-character string without terminating * zero. Some crazy files have embedded blanks in their * extensions, so only TRAILING blanks are insignificant. */ memset(sft_extension, 0, sizeof(sft_extension));; while (*src == ' ' && i--) /* skip traling blanks */ { dst--; src--; } if (i >= 0) while (i--) /* move whatever left */ *dst-- = *src--; /* Build Unix-style file permission bits. */ if ( !(sft_buf[fattr_ofs] & 0x07) ) /* no R, S or H bits set */ stat_buf->st_mode |= WRITE_ACCESS; /* Execute permission bits. fstat() cannot be called on * directories under DOS, so only executable programs/batch * files should be considered. */ if (_is_executable((const char *)0, fhandle, sft_extension)) stat_buf->st_mode |= EXEC_ACCESS; /* DOS 4.x and above seems to know about named pipes. */ if (dos_major > 3 && (sft_buf[6] & 0x20)) stat_buf->st_mode |= S_IFIFO; /* Device code. */ stat_buf->st_dev = drv_no; #ifdef HAVE_ST_RDEV stat_buf->st_rdev = drv_no; #endif /* The file's starting cluster number will serve as its * inode number. */ if ( (_djstat_flags & _STAT_INODE) == 0 && !is_remote) stat_buf->st_ino = *((unsigned short *)(sft_buf + clust_ofs)); /* If the cluster number returns zero (e.g., for empty files, * because DOS didn't allocate it a cluster yet) we have to * invent the inode using the file's name. We will use the * index into the SFT as part of unique identifier for our * file, so a possibility of two files with the same name * but different paths getting the same inode number is * minimized. * If we have a remote file, we invent inode even if there * is a non-zero number in the SFT, because it usually is * bogus (a left-over from last local file handle which used * the same SFT entry). * Note that we invent the inode even if is_remote is -1 * (i.e., IOCTL Func 0Ah failed), because that should mean * some network redirector grabs IOCTL functions in an * incompatible way. */ if ( (_djstat_flags & _STAT_INODE) == 0 && (stat_buf->st_ino == 0 || is_remote)) { static char name_pat[] = " :sft- \\ "; char name_buf[sizeof(name_pat)]; unsigned char *src_p = sft_buf + name_ofs + 7; char *dst_p = name_buf + 17; int j = 8; char *name_end; int first_digit = sft_idx / 100; int second_digit = (sft_idx - first_digit * 100) / 10; int third_digit = sft_idx - first_digit * 100 - second_digit * 10; /* Initialize the name buffer with zeroes, then * put in the drive letter and ``sft-XXX'', where * XXX is the index of our file entry in the SFT. */ strcpy(name_buf, name_pat); memset(name_buf + 10, 0, sizeof(name_buf) - 10); name_buf[0] = drv_no + 'A'; name_buf[6] = first_digit + '0'; name_buf[7] = second_digit + '0'; name_buf[8] = third_digit + '0'; /* Copy filename from SFT entry to local storage. * It is stored there in the infamous DOS format: * both name and extension are blank-padded, and no dot. * We cannot use strcpy, because the name might * include embedded blanks. Therefore we move the * characters from the end towards the beginning. */ while (*src_p == ' ' && j--) /* skip traling blanks */ { dst_p--; src_p--; } name_end = dst_p + 1; if (j >= 0) /* move whatever left */ while (j--) *dst_p-- = *src_p--; /* We've already got the extension. If it is non-empty, * insert a dot and copy the extension itself. */ if (sft_extension[0]) { *name_end++ = '.'; strcpy(name_end, sft_extension); } stat_buf->st_ino = _invent_inode(name_buf, dos_ftime, sft_fsize); _djstat_fail_bits |= _STFAIL_HASH; } /* Size, date and time. */ stat_buf->st_size = sft_fsize; stat_buf->st_atime = stat_buf->st_ctime = stat_buf->st_mtime = _file_time_stamp(dos_ftime); return 0; } _djstat_fail_bits |= _STFAIL_BADSFT; } /* Regular file, but DOS calls to find its length and time stamp * failed. This must be an illegal file handle, or something * else very, very funny... */ else return -1; /* errno set by filelength() or getftime() */ } /* Can't get SFT itself or can't find SFT entry belonging to our file. * This is probably unsupported variety of DOS, or other (not-so- * compatible) OS. * For these we supply whatever info we can find by conventional calls. */ if (have_trusted_values) { short dev_info = _get_dev_info(fhandle); /* IOCTL Function 0 */ if (dev_info == -1) return -1; /* errno set by get_dev_info() */ if (dev_info & 0x80) /* it's a device */ { if (_djstat_flags & _STAT_INODE) { /* We need the name of the device to invent an inode for it. * We cannot get the REAL name, because SFT info is unavailable. * If IOCTL tells us this is one of the standard devices, we * can make an educated guess. If not, we will invent inode * with no name. This will at least ensure that no two calls * accidentally get the same inode number. * We will also pretend devices belong to a special drive * named `@'. */ if (dev_info & 0xf) { char dev_name[16]; strcpy(dev_name, "@:\\dev\\"); if (dev_info & 3) /* either STDIN or STDOUT */ strcat(dev_name, "CON "); else if (dev_info & 4) /* NULL device */ strcat(dev_name, "NUL "); else if (dev_info & 8) /* CLOCK device */ strcat(dev_name, "CLOCK$ "); stat_buf->st_ino = _invent_inode(dev_name, 0, 0); } else stat_buf->st_ino = _invent_inode("", 0, 0); _djstat_fail_bits |= _STFAIL_HASH; } stat_buf->st_dev = -1; #ifdef HAVE_ST_RDEV stat_buf->st_rdev = -1; #endif stat_buf->st_mode |= (S_IFCHR | READ_ACCESS | WRITE_ACCESS); stat_buf->st_atime = stat_buf->st_mtime = time(0); dos_ftime = 0; stat_buf->st_ctime = _file_time_stamp(dos_ftime); } else { /* Regular file. The inode will be arbitrary, as we don't have * this file's name. Sigh... */ if ( (_djstat_flags & _STAT_INODE) == 0 ) { _djstat_fail_bits |= _STFAIL_HASH; stat_buf->st_ino = _invent_inode("", dos_ftime, trusted_fsize); } /* Return the minimum access bits every file has under DOS. */ stat_buf->st_mode |= (S_IFREG | READ_ACCESS); if (_djstat_flags & _STAT_ACCESS) _djstat_fail_bits |= _STFAIL_WRITEBIT; /* Executables are detected if they have magic numbers. */ if ( (_djstat_flags & _STAT_EXECBIT) && _is_executable((const char *)0, fhandle, (const char *)0)) stat_buf->st_mode |= EXEC_ACCESS; /* Lower 6 bits of IOCTL return value give the device number. */ stat_buf->st_dev = dev_info & 0x3f; #ifdef HAVE_ST_RDEV stat_buf->st_rdev = dev_info & 0x3f; #endif /* Novell Netware returns 0 drive number in the lower * 6 bits of dev_info. If this is what we get, return -2 * as drive number (it will be converted to '?' if added to 'A'). */ if (stat_buf->st_dev == 0) { stat_buf->st_dev = -2; #ifdef HAVE_ST_RDEV stat_buf->st_rdev = -2; #endif _djstat_fail_bits |= _STFAIL_DEVNO; } stat_buf->st_size = trusted_fsize; stat_buf->st_atime = stat_buf->st_ctime = stat_buf->st_mtime = _file_time_stamp(dos_ftime); } return 0; } /* Don't have even values from conventional DOS calls. * Give up completely on this funny handle. ERRNO is already * set by filelength() and/or getftime(). */ else return -1; } /* * Main entry point. This is a substitute for library fstat() function. */ int fstat(int handle, struct stat *statbuf) { int e = errno; /* save previous value of errno */ if (!statbuf) { errno = EFAULT; return -1; } if (fstat_assist(handle, statbuf) == -1) { return -1; /* already have ERRNO set by fstat_assist() */ } else { errno = e; return 0; } } #ifdef TEST #include <stdio.h> #include <fcntl.h> unsigned short _djstat_flags = 0; int main(int argc, char *argv[]) { struct stat stat_buf; int fd = -1; int i; char *endp; argc--; argv++; _djstat_flags = (unsigned short)strtoul(*argv, &endp, 0); /* Display 4 standard handles which are already open. */ for (i = 0; i <= 4; i++) { fstat(i, &stat_buf); fprintf(stderr, "handle-%d: %d %6u %o %d %d %ld %lu %s", i, stat_buf.st_dev, (unsigned)stat_buf.st_ino, stat_buf.st_mode, stat_buf.st_nlink, stat_buf.st_uid, (long)stat_buf.st_size, (unsigned long)stat_buf.st_mtime, ctime(&stat_buf.st_mtime)); _djstat_describe_lossage(stderr); } /* Now call fstat() for each command-line argument. */ while (++argv, --argc) { if (fd >= 19) close(fd); fd = open(*argv, O_RDONLY); if (fd != -1 && !fstat(fd, &stat_buf)) { fprintf(stderr, "%s (%d): %d %6u %o %d %d %ld %lu %s", *argv, fd, stat_buf.st_dev, (unsigned)stat_buf.st_ino, stat_buf.st_mode, stat_buf.st_nlink, stat_buf.st_uid, (long)stat_buf.st_size, (unsigned long)stat_buf.st_mtime, ctime(&stat_buf.st_mtime)); _djstat_describe_lossage(stderr); } else { fputs(*argv, stderr); perror(": failed to open/fstat"); _djstat_describe_lossage(stderr); } } return 0; } #endif /* TEST */