| 0,0 → 1,125 |
|---|
| /* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */ |
| /* IS_EXEC.C |
| * |
| * Given a filename or a file handle, and the extension of the file, |
| * determine if the file is executable. |
| * First, the file extension is checked in case it uniquely identifies |
| * the file as either an executable or not. Failing this, the first |
| * two bytes of the file are tested for known signatures of executable |
| * files. |
| * |
| * Copyright (c) 1994 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. |
| * |
| */ |
| |
| #include <libc/stubs.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <errno.h> |
| #include <libc/farptrgs.h> |
| #include <libc/dosio.h> |
| |
| extern unsigned short _djstat_flags; |
| unsigned short _get_magic(const char *, int); |
| int _is_executable(const char *, int, const char *); |
| |
| /* |
| * Read a MAGIC NUMBER from a given file. These are the first |
| * two bytes of the file, if we look at them as an unsigned short. */ |
| |
| #define _STAT_EXEC_EXT 2 /* get execute bits from file extension? */ |
| #define _STAT_EXEC_MAGIC 4 /* get execute bits from magic signature? */ |
| |
| unsigned short _get_magic(const char *s, int fh) |
| { |
| } |
| |
| /* A list of extensions which designate executable files. These |
| are NOT tested for the magic number. */ |
| static char executables[] = "|EXE|COM|BAT|BTM|DLL|VXD|"; |
| |
| /* A list of extensions which belong to files known to NEVER be |
| executables. These exist to minimize read()'ing files while |
| detecting executables by magic number. You are welcome to |
| add to this list, but remember: only extensions which could |
| NEVER be present in executables should go here. */ |
| static char non_executables[] = "\ |
| |A|A01|A02|A03|A04|A05|ADL|ARC|ARJ|ASC|ASM|AUX|AWK\ |
| |BAS|BIB|BGI|BMP\ |
| |C|CC|CFG|CGZ|CH3|CHR|CI|CLP|CMF|CPI|CPP|CXX\ |
| |DAT|DBF|DIZ|DOC|DVI\ |
| |E|EL|ELC\ |
| |F77|FN3\ |
| |GIF|GZ\ |
| |H|HLP|HPP|HXX\ |
| |ICO|IN|INC|INF|INI\ |
| |JPG\ |
| |L|LEX|LF|LIB|LOG|LST|LZH\ |
| |M|MAK|MAP|MF|MID|MPG\ |
| |O|OBJ\ |
| |PAK|PAS|PBM|PCD|PCX|PDS|PIC|PIF|PN3|PRJ|PS\ |
| |RAS|RGB|RLE\ |
| |S|SND|SY3\ |
| |TAR|TAZ|TEX|TGA|TGZ|TIF|TXH|TXI|TXT\ |
| |VOC\ |
| |WAV|WK1|WK3|WKB|WQ1|WQ3|WQ4|WQ5|WQ6|WQ!\ |
| |XBM\ |
| |Y\ |
| |ZIP|ZOO|"; |
| |
| int _is_executable(const char *filename, int fhandle, const char *extension) |
| { |
| if (!extension && filename) |
| { |
| const char *cp, *ep=0; |
| for (cp=filename; *cp; cp++) |
| { |
| if (*cp == '.') |
| ep = cp; |
| if (*cp == '/' || *cp == '\\' || *cp == ':') |
| ep = 0; |
| } |
| extension = ep; |
| } |
| if ((_djstat_flags & _STAT_EXEC_EXT) == 0 |
| && extension |
| && *extension |
| && strlen(extension) <= ((extension[0]=='.') ? 4 : 3)) |
| { |
| /* Search the list of extensions in executables[]. */ |
| char tmp_buf[6]; |
| |
| tmp_buf[0] = '|'; |
| strcpy(tmp_buf+1, *extension == '.' ? extension + 1 : extension); |
| strcat(tmp_buf, "|"); |
| if (strstr(non_executables, tmp_buf)) |
| return 0; |
| else if (strstr(executables, tmp_buf)) |
| return 1; |
| } |
| |
| /* No extension, or extension doesn't define execute |
| bits unambiguously. We are in for some dirty work. |
| Read the first two bytes of the file and see if they |
| are any of the known magic numbers which designate |
| executable files. |
| Unix-like shells, which have executable shell scripts |
| without extensions and DON'T have "#!" as their FIRST |
| TWO CHARACTERS, lose here. Sorry, folks. */ |
| if ( (_djstat_flags & _STAT_EXEC_MAGIC) == 0 ) |
| { |
| switch (_get_magic(filename, fhandle)) |
| { |
| case 0x5a4d: /* "MZ" */ |
| case 0x010b: |
| case 0x014c: |
| case 0x2123: /* "#!" */ |
| return 1; |
| } |
| } |
| |
| return 0; |
| } |