/* $OpenBSD: misc.c,v 1.37 2009/04/19 20:34:05 sthen Exp $ */ /* $OpenBSD: path.c,v 1.12 2005/03/30 17:16:37 deraadt Exp $ */ /*- * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, * 2011, 2012 * Thorsten Glaser * * Provided that these terms and disclaimer and all copyright notices * are retained or reproduced in an accompanying document, permission * is granted to deal in this work without restriction, including un- * limited rights to use, publicly perform, distribute, sell, modify, * merge, give away, or sublicence. * * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to * the utmost extent permitted by applicable law, neither express nor * implied; without malicious intent or gross negligence. In no event * may a licensor, author or contributor be held liable for indirect, * direct, other damage, loss, or other issues arising in any way out * of dealing in the work, even if advised of the possibility of such * damage or existence of a defect, except proven that it results out * of said person's immediate fault when using the work as intended. */ #include "sh.h" #if !HAVE_GETRUSAGE #include #endif #if HAVE_GRP_H #include #endif __RCSID("$MirOS: src/bin/mksh/misc.c,v 1.186 2012/04/01 16:55:16 tg Exp $"); /* type bits for unsigned char */ unsigned char chtypes[UCHAR_MAX + 1]; static const unsigned char *pat_scan(const unsigned char *, const unsigned char *, bool); static int do_gmatch(const unsigned char *, const unsigned char *, const unsigned char *, const unsigned char *); static const unsigned char *cclass(const unsigned char *, int); #ifdef TIOCSCTTY static void chvt(const char *); #endif /*XXX this should go away */ static int make_path(const char *, const char *, char **, XString *, int *); #ifdef SETUID_CAN_FAIL_WITH_EAGAIN /* we don't need to check for other codes, EPERM won't happen */ #define DO_SETUID(func, argvec) do { \ if ((func argvec) && errno == EAGAIN) \ errorf("%s failed with EAGAIN, probably due to a" \ " too low process limit; aborting", #func); \ } while (/* CONSTCOND */ 0) #else #define DO_SETUID(func, argvec) func argvec #endif /* * Fast character classes */ void setctypes(const char *s, int t) { unsigned int i; if (t & C_IFS) { for (i = 0; i < UCHAR_MAX + 1; i++) chtypes[i] &= ~C_IFS; /* include \0 in C_IFS */ chtypes[0] |= C_IFS; } while (*s != 0) chtypes[(unsigned char)*s++] |= t; } void initctypes(void) { int c; for (c = 'a'; c <= 'z'; c++) chtypes[c] |= C_ALPHA; for (c = 'A'; c <= 'Z'; c++) chtypes[c] |= C_ALPHA; chtypes['_'] |= C_ALPHA; setctypes("0123456789", C_DIGIT); /* \0 added automatically */ setctypes(" \t\n|&;<>()", C_LEX1); setctypes("*@#!$-?", C_VAR1); setctypes(" \t\n", C_IFSWS); setctypes("=-+?", C_SUBOP1); setctypes("\t\n \"#$&'()*;<=>?[\\]`|", C_QUOTE); } /* called from XcheckN() to grow buffer */ char * Xcheck_grow(XString *xsp, const char *xp, size_t more) { const char *old_beg = xsp->beg; if (more < xsp->len) more = xsp->len; /* (xsp->len + X_EXTRA) never overflows */ checkoktoadd(more, xsp->len + X_EXTRA); xsp->beg = aresize(xsp->beg, (xsp->len += more) + X_EXTRA, xsp->areap); xsp->end = xsp->beg + xsp->len; return (xsp->beg + (xp - old_beg)); } #define SHFLAGS_DEFNS #include "sh_flags.h" const struct shoption options[] = { #define SHFLAGS_ITEMS #include "sh_flags.h" }; /* * translate -o option into F* constant (also used for test -o option) */ size_t option(const char *n) { size_t i; if ((n[0] == '-' || n[0] == '+') && n[1] && !n[2]) { for (i = 0; i < NELEM(options); i++) if (options[i].c == n[1]) return (i); } else for (i = 0; i < NELEM(options); i++) if (options[i].name && strcmp(options[i].name, n) == 0) return (i); return ((size_t)-1); } struct options_info { int opt_width; int opts[NELEM(options)]; }; static char *options_fmt_entry(char *, size_t, int, const void *); static void printoptions(bool); /* format a single select menu item */ static char * options_fmt_entry(char *buf, size_t buflen, int i, const void *arg) { const struct options_info *oi = (const struct options_info *)arg; shf_snprintf(buf, buflen, "%-*s %s", oi->opt_width, options[oi->opts[i]].name, Flag(oi->opts[i]) ? "on" : "off"); return (buf); } static void printoptions(bool verbose) { size_t i = 0; if (verbose) { ssize_t n = 0, len, octs = 0; struct options_info oi; /* verbose version */ shf_puts("Current option settings\n", shl_stdout); oi.opt_width = 0; while (i < NELEM(options)) { if (options[i].name) { oi.opts[n++] = i; len = strlen(options[i].name); if (len > octs) octs = len; len = utf_mbswidth(options[i].name); if (len > oi.opt_width) oi.opt_width = len; } ++i; } print_columns(shl_stdout, n, options_fmt_entry, &oi, octs + 4, oi.opt_width + 4, true); } else { /* short version like AT&T ksh93 */ shf_puts(Tset, shl_stdout); while (i < (int)NELEM(options)) { if (Flag(i) && options[i].name) shprintf("%s %s %s", null, "-o", options[i].name); ++i; } shf_putc('\n', shl_stdout); } } char * getoptions(void) { size_t i; char m[(int)FNFLAGS + 1]; char *cp = m; for (i = 0; i < NELEM(options); i++) if (options[i].c && Flag(i)) *cp++ = options[i].c; strndupx(cp, m, cp - m, ATEMP); return (cp); } /* change a Flag(*) value; takes care of special actions */ void change_flag(enum sh_flag f, int what, unsigned int newval) { unsigned char oldval; oldval = Flag(f); /* needed for tristates */ Flag(f) = newval ? 1 : 0; #ifndef MKSH_UNEMPLOYED if (f == FMONITOR) { if (what != OF_CMDLINE && newval != oldval) j_change(); } else #endif if (( #if !MKSH_S_NOVI f == FVI || #endif f == FEMACS || f == FGMACS) && newval) { #if !MKSH_S_NOVI Flag(FVI) = #endif Flag(FEMACS) = Flag(FGMACS) = 0; Flag(f) = (unsigned char)newval; } else if (f == FPRIVILEGED && oldval && !newval) { /* Turning off -p? */ /*XXX this can probably be optimised */ kshegid = kshgid = getgid(); #if HAVE_SETRESUGID DO_SETUID(setresgid, (kshegid, kshegid, kshegid)); #if HAVE_SETGROUPS /* setgroups doesn't EAGAIN on Linux */ setgroups(1, &kshegid); #endif DO_SETUID(setresuid, (ksheuid, ksheuid, ksheuid)); #else /* seteuid, setegid, setgid don't EAGAIN on Linux */ ksheuid = kshuid = getuid(); #ifndef __BEOS__ /* BeOS doesn't have different UIDs */ seteuid(ksheuid); #endif DO_SETUID(setuid, (ksheuid)); #ifndef __BEOS__ /* BeOS doesn't have different GIDs */ setegid(kshegid); #endif setgid(kshegid); #endif } else if ((f == FPOSIX || f == FSH) && newval) { Flag(FPOSIX) = Flag(FSH) = Flag(FBRACEEXPAND) = 0; Flag(f) = (unsigned char)newval; } /* Changing interactive flag? */ if (f == FTALKING) { if ((what == OF_CMDLINE || what == OF_SET) && procpid == kshpid) Flag(FTALKING_I) = (unsigned char)newval; } } /* * Parse command line and set command arguments. Returns the index of * non-option arguments, -1 if there is an error. */ int parse_args(const char **argv, /* OF_CMDLINE or OF_SET */ int what, bool *setargsp) { static char cmd_opts[NELEM(options) + 5]; /* o:T:\0 */ static char set_opts[NELEM(options) + 6]; /* A:o;s\0 */ char set, *opts; const char *array = NULL; Getopt go; size_t i; int optc, arrayset = 0; bool sortargs = false; /* First call? Build option strings... */ if (cmd_opts[0] == '\0') { char *p = cmd_opts, *q = set_opts; /* see cmd_opts[] declaration */ *p++ = 'o'; *p++ = ':'; #if !defined(MKSH_SMALL) || defined(TIOCSCTTY) *p++ = 'T'; *p++ = ':'; #endif /* see set_opts[] declaration */ *q++ = 'A'; *q++ = ':'; *q++ = 'o'; *q++ = ';'; *q++ = 's'; for (i = 0; i < NELEM(options); i++) { if (options[i].c) { if (options[i].flags & OF_CMDLINE) *p++ = options[i].c; if (options[i].flags & OF_SET) *q++ = options[i].c; } } *p = '\0'; *q = '\0'; } if (what == OF_CMDLINE) { const char *p = argv[0], *q; /* * Set FLOGIN before parsing options so user can clear * flag using +l. */ if (*p != '-') for (q = p; *q; ) if (*q++ == '/') p = q; Flag(FLOGIN) = (*p == '-'); opts = cmd_opts; } else if (what == OF_FIRSTTIME) { opts = cmd_opts; } else opts = set_opts; ksh_getopt_reset(&go, GF_ERROR|GF_PLUSOPT); while ((optc = ksh_getopt(argv, &go, opts)) != -1) { set = (go.info & GI_PLUS) ? 0 : 1; switch (optc) { case 'A': if (what == OF_FIRSTTIME) break; arrayset = set ? 1 : -1; array = go.optarg; break; case 'o': if (what == OF_FIRSTTIME) break; if (go.optarg == NULL) { /* * lone -o: print options * * Note that on the command line, -o requires * an option (ie, can't get here if what is * OF_CMDLINE). */ printoptions(set); break; } i = option(go.optarg); if ((i != (size_t)-1) && set == Flag(i)) /* * Don't check the context if the flag * isn't changing - makes "set -o interactive" * work if you're already interactive. Needed * if the output of "set +o" is to be used. */ ; else if ((i != (size_t)-1) && (options[i].flags & what)) change_flag((enum sh_flag)i, what, set); else { bi_errorf("%s: %s", go.optarg, "bad option"); return (-1); } break; #if !defined(MKSH_SMALL) || defined(TIOCSCTTY) case 'T': if (what != OF_FIRSTTIME) break; #ifndef TIOCSCTTY errorf("no TIOCSCTTY ioctl"); #else change_flag(FTALKING, OF_CMDLINE, 1); chvt(go.optarg); break; #endif #endif case '?': return (-1); default: if (what == OF_FIRSTTIME) break; /* -s: sort positional params (AT&T ksh stupidity) */ if (what == OF_SET && optc == 's') { sortargs = true; break; } for (i = 0; i < NELEM(options); i++) if (optc == options[i].c && (what & options[i].flags)) { change_flag((enum sh_flag)i, what, set); break; } if (i == NELEM(options)) internal_errorf("parse_args: '%c'", optc); } } if (!(go.info & GI_MINUSMINUS) && argv[go.optind] && (argv[go.optind][0] == '-' || argv[go.optind][0] == '+') && argv[go.optind][1] == '\0') { /* lone - clears -v and -x flags */ if (argv[go.optind][0] == '-') Flag(FVERBOSE) = Flag(FXTRACE) = 0; /* set skips lone - or + option */ go.optind++; } if (setargsp) /* -- means set $#/$* even if there are no arguments */ *setargsp = !arrayset && ((go.info & GI_MINUSMINUS) || argv[go.optind]); if (arrayset) { const char *ccp = NULL; if (*array) ccp = skip_varname(array, false); if (!ccp || !(!ccp[0] || (ccp[0] == '+' && !ccp[1]))) { bi_errorf("%s: %s", array, "is not an identifier"); return (-1); } } if (sortargs) { for (i = go.optind; argv[i]; i++) ; qsort(&argv[go.optind], i - go.optind, sizeof(void *), xstrcmp); } if (arrayset) go.optind += set_array(array, tobool(arrayset > 0), argv + go.optind); return (go.optind); } /* parse a decimal number: returns 0 if string isn't a number, 1 otherwise */ int getn(const char *s, int *ai) { int i, c, rv = 0; bool neg = false; do { c = *s++; } while (ksh_isspace(c)); if (c == '-') { neg = true; c = *s++; } else if (c == '+') c = *s++; *ai = i = 0; do { if (!ksh_isdigit(c)) goto getn_out; i *= 10; if (i < *ai) /* overflow */ goto getn_out; i += c - '0'; *ai = i; } while ((c = *s++)); rv = 1; getn_out: if (neg) *ai = -*ai; return (rv); } /* getn() that prints error */ int bi_getn(const char *as, int *ai) { int rv; if (!(rv = getn(as, ai))) bi_errorf("%s: %s", as, "bad number"); return (rv); } /** * pattern simplifications: * - @(x) -> x (not @(x|y) though) * - ** -> * */ static void * simplify_gmatch_pattern(const unsigned char *sp) { uint8_t c; unsigned char *cp, *dp; const unsigned char *ps, *se; cp = alloc(strlen((const void *)sp) + 1, ATEMP); goto simplify_gmatch_pat1a; /* foo@(b@(a)r)b@(a|a)z -> foobarb@(a|a)z */ simplify_gmatch_pat1: sp = cp; simplify_gmatch_pat1a: dp = cp; se = sp + strlen((const void *)sp); while ((c = *sp++)) { if (!ISMAGIC(c)) { *dp++ = c; continue; } switch ((c = *sp++)) { case 0x80|'@': /* simile for @ */ case 0x80|' ': /* check whether it has only one clause */ ps = pat_scan(sp, se, true); if (!ps || ps[-1] != /*(*/ ')') /* nope */ break; /* copy inner clause until matching close */ ps -= 2; while ((const unsigned char *)sp < ps) *dp++ = *sp++; /* skip MAGIC and closing parenthesis */ sp += 2; /* copy the rest of the pattern */ memmove(dp, sp, strlen((const void *)sp) + 1); /* redo from start */ goto simplify_gmatch_pat1; } *dp++ = MAGIC; *dp++ = c; } *dp = '\0'; /* collapse adjacent asterisk wildcards */ sp = dp = cp; while ((c = *sp++)) { if (!ISMAGIC(c)) { *dp++ = c; continue; } switch ((c = *sp++)) { case '*': while (ISMAGIC(sp[0]) && sp[1] == c) sp += 2; break; } *dp++ = MAGIC; *dp++ = c; } *dp = '\0'; /* return the result, allocated from ATEMP */ return (cp); } /* -------- gmatch.c -------- */ /* * int gmatch(string, pattern) * char *string, *pattern; * * Match a pattern as in sh(1). * pattern character are prefixed with MAGIC by expand. */ int gmatchx(const char *s, const char *p, bool isfile) { const char *se, *pe; char *pnew; int rv; if (s == NULL || p == NULL) return (0); se = s + strlen(s); pe = p + strlen(p); /* * isfile is false iff no syntax check has been done on * the pattern. If check fails, just to a strcmp(). */ if (!isfile && !has_globbing(p, pe)) { size_t len = pe - p + 1; char tbuf[64]; char *t = len <= sizeof(tbuf) ? tbuf : alloc(len, ATEMP); debunk(t, p, len); return (!strcmp(t, s)); } /* * since the do_gmatch() engine sucks so much, we must do some * pattern simplifications */ pnew = simplify_gmatch_pattern((const unsigned char *)p); pe = pnew + strlen(pnew); rv = do_gmatch((const unsigned char *)s, (const unsigned char *)se, (const unsigned char *)pnew, (const unsigned char *)pe); afree(pnew, ATEMP); return (rv); } /** * Returns if p is a syntacticly correct globbing pattern, false * if it contains no pattern characters or if there is a syntax error. * Syntax errors are: * - [ with no closing ] * - imbalanced $(...) expression * - [...] and *(...) not nested (eg, [a$(b|]c), *(a[b|c]d)) */ /*XXX * - if no magic, * if dest given, copy to dst * return ? * - if magic && (no globbing || syntax error) * debunk to dst * return ? * - return ? */ int has_globbing(const char *xp, const char *xpe) { const unsigned char *p = (const unsigned char *) xp; const unsigned char *pe = (const unsigned char *) xpe; int c; int nest = 0, bnest = 0; bool saw_glob = false; /* inside [...] */ bool in_bracket = false; for (; p < pe; p++) { if (!ISMAGIC(*p)) continue; if ((c = *++p) == '*' || c == '?') saw_glob = true; else if (c == '[') { if (!in_bracket) { saw_glob = true; in_bracket = true; if (ISMAGIC(p[1]) && p[2] == '!') p += 2; if (ISMAGIC(p[1]) && p[2] == ']') p += 2; } /*XXX Do we need to check ranges here? POSIX Q */ } else if (c == ']') { if (in_bracket) { if (bnest) /* [a*(b]) */ return (0); in_bracket = false; } } else if ((c & 0x80) && vstrchr("*+?@! ", c & 0x7f)) { saw_glob = true; if (in_bracket) bnest++; else nest++; } else if (c == '|') { if (in_bracket && !bnest) /* *(a[foo|bar]) */ return (0); } else if (c == /*(*/ ')') { if (in_bracket) { if (!bnest--) /* *(a[b)c] */ return (0); } else if (nest) nest--; } /* * else must be a MAGIC-MAGIC, or MAGIC-!, * MAGIC--, MAGIC-], MAGIC-{, MAGIC-, MAGIC-} */ } return (saw_glob && !in_bracket && !nest); } /* Function must return either 0 or 1 (assumed by code for 0x80|'!') */ static int do_gmatch(const unsigned char *s, const unsigned char *se, const unsigned char *p, const unsigned char *pe) { int sc, pc; const unsigned char *prest, *psub, *pnext; const unsigned char *srest; if (s == NULL || p == NULL) return (0); while (p < pe) { pc = *p++; sc = s < se ? *s : '\0'; s++; if (!ISMAGIC(pc)) { if (sc != pc) return (0); continue; } switch (*p++) { case '[': if (sc == 0 || (p = cclass(p, sc)) == NULL) return (0); break; case '?': if (sc == 0) return (0); if (UTFMODE) { --s; s += utf_ptradj((const void *)s); } break; case '*': if (p == pe) return (1); s--; do { if (do_gmatch(s, se, p, pe)) return (1); } while (s++ < se); return (0); /** * [*+?@!](pattern|pattern|..) * This is also needed for ${..%..}, etc. */ /* matches one or more times */ case 0x80|'+': /* matches zero or more times */ case 0x80|'*': if (!(prest = pat_scan(p, pe, false))) return (0); s--; /* take care of zero matches */ if (p[-1] == (0x80 | '*') && do_gmatch(s, se, prest, pe)) return (1); for (psub = p; ; psub = pnext) { pnext = pat_scan(psub, pe, true); for (srest = s; srest <= se; srest++) { if (do_gmatch(s, srest, psub, pnext - 2) && (do_gmatch(srest, se, prest, pe) || (s != srest && do_gmatch(srest, se, p - 2, pe)))) return (1); } if (pnext == prest) break; } return (0); /* matches zero or once */ case 0x80|'?': /* matches one of the patterns */ case 0x80|'@': /* simile for @ */ case 0x80|' ': if (!(prest = pat_scan(p, pe, false))) return (0); s--; /* Take care of zero matches */ if (p[-1] == (0x80 | '?') && do_gmatch(s, se, prest, pe)) return (1); for (psub = p; ; psub = pnext) { pnext = pat_scan(psub, pe, true); srest = prest == pe ? se : s; for (; srest <= se; srest++) { if (do_gmatch(s, srest, psub, pnext - 2) && do_gmatch(srest, se, prest, pe)) return (1); } if (pnext == prest) break; } return (0); /* matches none of the patterns */ case 0x80|'!': if (!(prest = pat_scan(p, pe, false))) return (0); s--; for (srest = s; srest <= se; srest++) { int matched = 0; for (psub = p; ; psub = pnext) { pnext = pat_scan(psub, pe, true); if (do_gmatch(s, srest, psub, pnext - 2)) { matched = 1; break; } if (pnext == prest) break; } if (!matched && do_gmatch(srest, se, prest, pe)) return (1); } return (0); default: if (sc != p[-1]) return (0); break; } } return (s == se); } static const unsigned char * cclass(const unsigned char *p, int sub) { int c, d, notp, found = 0; const unsigned char *orig_p = p; if ((notp = (ISMAGIC(*p) && *++p == '!'))) p++; do { c = *p++; if (ISMAGIC(c)) { c = *p++; if ((c & 0x80) && !ISMAGIC(c)) { /* extended pattern matching: *+?@! */ c &= 0x7F; /* XXX the ( char isn't handled as part of [] */ if (c == ' ') /* simile for @: plain (..) */ c = '(' /*)*/; } } if (c == '\0') /* No closing ] - act as if the opening [ was quoted */ return (sub == '[' ? orig_p : NULL); if (ISMAGIC(p[0]) && p[1] == '-' && (!ISMAGIC(p[2]) || p[3] != ']')) { /* MAGIC- */ p += 2; d = *p++; if (ISMAGIC(d)) { d = *p++; if ((d & 0x80) && !ISMAGIC(d)) d &= 0x7f; } /* POSIX says this is an invalid expression */ if (c > d) return (NULL); } else d = c; if (c == sub || (c <= sub && sub <= d)) found = 1; } while (!(ISMAGIC(p[0]) && p[1] == ']')); return ((found != notp) ? p+2 : NULL); } /* Look for next ) or | (if match_sep) in *(foo|bar) pattern */ static const unsigned char * pat_scan(const unsigned char *p, const unsigned char *pe, bool match_sep) { int nest = 0; for (; p < pe; p++) { if (!ISMAGIC(*p)) continue; if ((*++p == /*(*/ ')' && nest-- == 0) || (*p == '|' && match_sep && nest == 0)) return (p + 1); if ((*p & 0x80) && vstrchr("*+?@! ", *p & 0x7f)) nest++; } return (NULL); } int xstrcmp(const void *p1, const void *p2) { return (strcmp(*(const char * const *)p1, *(const char * const *)p2)); } /* Initialise a Getopt structure */ void ksh_getopt_reset(Getopt *go, int flags) { go->optind = 1; go->optarg = NULL; go->p = 0; go->flags = flags; go->info = 0; go->buf[1] = '\0'; } /** * getopt() used for shell built-in commands, the getopts command, and * command line options. * A leading ':' in options means don't print errors, instead return '?' * or ':' and set go->optarg to the offending option character. * If GF_ERROR is set (and option doesn't start with :), errors result in * a call to bi_errorf(). * * Non-standard features: * - ';' is like ':' in options, except the argument is optional * (if it isn't present, optarg is set to 0). * Used for 'set -o'. * - ',' is like ':' in options, except the argument always immediately * follows the option character (optarg is set to the null string if * the option is missing). * Used for 'read -u2', 'print -u2' and fc -40. * - '#' is like ':' in options, expect that the argument is optional * and must start with a digit. If the argument doesn't start with a * digit, it is assumed to be missing and normal option processing * continues (optarg is set to 0 if the option is missing). * Used for 'typeset -LZ4'. * - accepts +c as well as -c IF the GF_PLUSOPT flag is present. If an * option starting with + is accepted, the GI_PLUS flag will be set * in go->info. */ int ksh_getopt(const char **argv, Getopt *go, const char *optionsp) { char c; const char *o; if (go->p == 0 || (c = argv[go->optind - 1][go->p]) == '\0') { const char *arg = argv[go->optind], flag = arg ? *arg : '\0'; go->p = 1; if (flag == '-' && arg[1] == '-' && arg[2] == '\0') { go->optind++; go->p = 0; go->info |= GI_MINUSMINUS; return (-1); } if (arg == NULL || ((flag != '-' ) && /* neither a - nor a + (if + allowed) */ (!(go->flags & GF_PLUSOPT) || flag != '+')) || (c = arg[1]) == '\0') { go->p = 0; return (-1); } go->optind++; go->info &= ~(GI_MINUS|GI_PLUS); go->info |= flag == '-' ? GI_MINUS : GI_PLUS; } go->p++; if (c == '?' || c == ':' || c == ';' || c == ',' || c == '#' || !(o = cstrchr(optionsp, c))) { if (optionsp[0] == ':') { go->buf[0] = c; go->optarg = go->buf; } else { warningf(true, "%s%s-%c: %s", (go->flags & GF_NONAME) ? "" : argv[0], (go->flags & GF_NONAME) ? "" : ": ", c, "unknown option"); if (go->flags & GF_ERROR) bi_errorfz(); } return ('?'); } /** * : means argument must be present, may be part of option argument * or the next argument * ; same as : but argument may be missing * , means argument is part of option argument, and may be null. */ if (*++o == ':' || *o == ';') { if (argv[go->optind - 1][go->p]) go->optarg = argv[go->optind - 1] + go->p; else if (argv[go->optind]) go->optarg = argv[go->optind++]; else if (*o == ';') go->optarg = NULL; else { if (optionsp[0] == ':') { go->buf[0] = c; go->optarg = go->buf; return (':'); } warningf(true, "%s%s-%c: %s", (go->flags & GF_NONAME) ? "" : argv[0], (go->flags & GF_NONAME) ? "" : ": ", c, "requires an argument"); if (go->flags & GF_ERROR) bi_errorfz(); return ('?'); } go->p = 0; } else if (*o == ',') { /* argument is attached to option character, even if null */ go->optarg = argv[go->optind - 1] + go->p; go->p = 0; } else if (*o == '#') { /* * argument is optional and may be attached or unattached * but must start with a digit. optarg is set to 0 if the * argument is missing. */ if (argv[go->optind - 1][go->p]) { if (ksh_isdigit(argv[go->optind - 1][go->p])) { go->optarg = argv[go->optind - 1] + go->p; go->p = 0; } else go->optarg = NULL; } else { if (argv[go->optind] && ksh_isdigit(argv[go->optind][0])) { go->optarg = argv[go->optind++]; go->p = 0; } else go->optarg = NULL; } } return (c); } /* * print variable/alias value using necessary quotes * (POSIX says they should be suitable for re-entry...) * No trailing newline is printed. */ void print_value_quoted(struct shf *shf, const char *s) { unsigned char c; const unsigned char *p = (const unsigned char *)s; bool inquote = true; /* first, check whether any quotes are needed */ while ((c = *p++) >= 32) if (ctype(c, C_QUOTE)) inquote = false; p = (const unsigned char *)s; if (c == 0) { if (inquote) { /* nope, use the shortcut */ shf_puts(s, shf); return; } /* otherwise, quote nicely via state machine */ while ((c = *p++) != 0) { if (c == '\'') { /* * multiple single quotes or any of them * at the beginning of a string look nicer * this way than when simply substituting */ if (inquote) { shf_putc('\'', shf); inquote = false; } shf_putc('\\', shf); } else if (!inquote) { shf_putc('\'', shf); inquote = true; } shf_putc(c, shf); } } else { unsigned int wc; size_t n; /* use $'...' quote format */ shf_putc('$', shf); shf_putc('\'', shf); while ((c = *p) != 0) { if (c >= 0xC2) { n = utf_mbtowc(&wc, (const char *)p); if (n != (size_t)-1) { p += n; shf_fprintf(shf, "\\u%04X", wc); continue; } } ++p; switch (c) { /* see unbksl() in this file for comments */ case 7: c = 'a'; if (0) /* FALLTHROUGH */ case '\b': c = 'b'; if (0) /* FALLTHROUGH */ case '\f': c = 'f'; if (0) /* FALLTHROUGH */ case '\n': c = 'n'; if (0) /* FALLTHROUGH */ case '\r': c = 'r'; if (0) /* FALLTHROUGH */ case '\t': c = 't'; if (0) /* FALLTHROUGH */ case 11: c = 'v'; if (0) /* FALLTHROUGH */ case '\033': /* take E not e because \e is \ in *roff */ c = 'E'; /* FALLTHROUGH */ case '\\': shf_putc('\\', shf); if (0) /* FALLTHROUGH */ default: if (c < 32 || c > 0x7E) { /* FALLTHROUGH */ case '\'': shf_fprintf(shf, "\\x%02X", c); break; } shf_putc(c, shf); break; } } inquote = true; } if (inquote) shf_putc('\'', shf); } /* * Print things in columns and rows - func() is called to format * the i-th element */ void print_columns(struct shf *shf, int n, char *(*func)(char *, size_t, int, const void *), const void *arg, size_t max_oct, size_t max_colz, bool prefcol) { int i, r, c, rows, cols, nspace, max_col; char *str; if (n <= 0) { #ifndef MKSH_SMALL internal_warningf("print_columns called with n=%d <= 0", n); #endif return; } if (max_colz > 2147483647) { #ifndef MKSH_SMALL internal_warningf("print_columns called with max_col=%zu > INT_MAX", max_colz); #endif return; } max_col = (int)max_colz; ++max_oct; str = alloc(max_oct, ATEMP); /* * We use (max_col + 1) to consider the space separator. * Note that no space is printed after the last column * to avoid problems with terminals that have auto-wrap. */ cols = x_cols / (max_col + 1); /* if we can only print one column anyway, skip the goo */ if (cols < 2) { for (i = 0; i < n; ++i) shf_fprintf(shf, "%s \n", (*func)(str, max_oct, i, arg)); goto out; } rows = (n + cols - 1) / cols; if (prefcol && cols > rows) { i = rows; rows = cols > n ? n : cols; cols = i; } max_col = -max_col; nspace = (x_cols + max_col * cols) / cols; if (nspace <= 0) nspace = 1; for (r = 0; r < rows; r++) { for (c = 0; c < cols; c++) { i = c * rows + r; if (i < n) { shf_fprintf(shf, "%*s", max_col, (*func)(str, max_oct, i, arg)); if (c + 1 < cols) shf_fprintf(shf, "%*s", nspace, null); } } shf_putchar('\n', shf); } out: afree(str, ATEMP); } /* Strip any nul bytes from buf - returns new length (nbytes - # of nuls) */ void strip_nuls(char *buf, int nbytes) { char *dst; /* * nbytes check because some systems (older FreeBSDs) have a * buggy memchr() */ if (nbytes && (dst = memchr(buf, '\0', nbytes))) { char *end = buf + nbytes; char *p, *q; for (p = dst; p < end; p = q) { /* skip a block of nulls */ while (++p < end && *p == '\0') ; /* find end of non-null block */ if (!(q = memchr(p, '\0', end - p))) q = end; memmove(dst, p, q - p); dst += q - p; } *dst = '\0'; } } /* * Like read(2), but if read fails due to non-blocking flag, * resets flag and restarts read. */ ssize_t blocking_read(int fd, char *buf, size_t nbytes) { ssize_t ret; bool tried_reset = false; while ((ret = read(fd, buf, nbytes)) < 0) { if (!tried_reset && errno == EAGAIN) { if (reset_nonblock(fd) > 0) { tried_reset = true; continue; } errno = EAGAIN; } break; } return (ret); } /* * Reset the non-blocking flag on the specified file descriptor. * Returns -1 if there was an error, 0 if non-blocking wasn't set, * 1 if it was. */ int reset_nonblock(int fd) { int flags; if ((flags = fcntl(fd, F_GETFL, 0)) < 0) return (-1); if (!(flags & O_NONBLOCK)) return (0); flags &= ~O_NONBLOCK; if (fcntl(fd, F_SETFL, flags) < 0) return (-1); return (1); } /* getcwd(3) equivalent, allocates from ATEMP but doesn't resize */ char * ksh_get_wd(void) { #ifdef NO_PATH_MAX char *rv, *cp; if ((cp = get_current_dir_name())) { strdupx(rv, cp, ATEMP); free_gnu_gcdn(cp); } else rv = NULL; #else char *rv; if (!getcwd((rv = alloc(PATH_MAX + 1, ATEMP)), PATH_MAX)) { afree(rv, ATEMP); rv = NULL; } #endif return (rv); } #ifndef ELOOP #define ELOOP E2BIG #endif char * do_realpath(const char *upath) { char *xp, *ip, *tp, *ipath, *ldest = NULL; XString xs; ptrdiff_t pos; size_t len; int llen; struct stat sb; #ifdef NO_PATH_MAX size_t ldestlen = 0; #define pathlen sb.st_size #define pathcnd (ldestlen < (pathlen + 1)) #else #define pathlen PATH_MAX #define pathcnd (!ldest) #endif /* max. recursion depth */ int symlinks = 32; if (upath[0] == '/') { /* upath is an absolute pathname */ strdupx(ipath, upath, ATEMP); } else { /* upath is a relative pathname, prepend cwd */ if ((tp = ksh_get_wd()) == NULL || tp[0] != '/') return (NULL); ipath = shf_smprintf("%s%s%s", tp, "/", upath); afree(tp, ATEMP); } /* ipath and upath are in memory at the same time -> unchecked */ Xinit(xs, xp, strlen(ip = ipath) + 1, ATEMP); /* now jump into the deep of the loop */ goto beginning_of_a_pathname; while (*ip) { /* skip slashes in input */ while (*ip == '/') ++ip; if (!*ip) break; /* get next pathname component from input */ tp = ip; while (*ip && *ip != '/') ++ip; len = ip - tp; /* check input for "." and ".." */ if (tp[0] == '.') { if (len == 1) /* just continue with the next one */ continue; else if (len == 2 && tp[1] == '.') { /* strip off last pathname component */ while (xp > Xstring(xs, xp)) if (*--xp == '/') break; /* then continue with the next one */ continue; } } /* store output position away, then append slash to output */ pos = Xsavepos(xs, xp); /* 1 for the '/' and len + 1 for tp and the NUL from below */ XcheckN(xs, xp, 1 + len + 1); Xput(xs, xp, '/'); /* append next pathname component to output */ memcpy(xp, tp, len); xp += len; *xp = '\0'; /* lstat the current output, see if it's a symlink */ if (lstat(Xstring(xs, xp), &sb)) { /* lstat failed */ if (errno == ENOENT) { /* because the pathname does not exist */ while (*ip == '/') /* skip any trailing slashes */ ++ip; /* no more components left? */ if (!*ip) /* we can still return successfully */ break; /* more components left? fall through */ } /* not ENOENT or not at the end of ipath */ goto notfound; } /* check if we encountered a symlink? */ if (S_ISLNK(sb.st_mode)) { /* reached maximum recursion depth? */ if (!symlinks--) { /* yep, prevent infinite loops */ errno = ELOOP; goto notfound; } /* get symlink(7) target */ if (pathcnd) { #ifdef NO_PATH_MAX if (notoktoadd(pathlen, 1)) { errno = ENAMETOOLONG; goto notfound; } #endif ldest = aresize(ldest, pathlen + 1, ATEMP); } llen = readlink(Xstring(xs, xp), ldest, pathlen); if (llen < 0) /* oops... */ goto notfound; ldest[llen] = '\0'; /* * restart if symlink target is an absolute path, * otherwise continue with currently resolved prefix */ /* append rest of current input path to link target */ tp = shf_smprintf("%s%s%s", ldest, *ip ? "/" : "", ip); afree(ipath, ATEMP); ip = ipath = tp; if (ldest[0] != '/') { /* symlink target is a relative path */ xp = Xrestpos(xs, xp, pos); } else { /* symlink target is an absolute path */ xp = Xstring(xs, xp); beginning_of_a_pathname: /* assert: (ip == ipath)[0] == '/' */ /* assert: xp == xs.beg => start of path */ /* exactly two leading slashes? (SUSv4 3.266) */ if (ip[1] == '/' && ip[2] != '/') { /* keep them, e.g. for UNC pathnames */ Xput(xs, xp, '/'); } } } /* otherwise (no symlink) merely go on */ } /* * either found the target and successfully resolved it, * or found its parent directory and may create it */ if (Xlength(xs, xp) == 0) /* * if the resolved pathname is "", make it "/", * otherwise do not add a trailing slash */ Xput(xs, xp, '/'); Xput(xs, xp, '\0'); /* * if source path had a trailing slash, check if target path * is not a non-directory existing file */ if (ip > ipath && ip[-1] == '/') { if (stat(Xstring(xs, xp), &sb)) { if (errno != ENOENT) goto notfound; } else if (!S_ISDIR(sb.st_mode)) { errno = ENOTDIR; goto notfound; } /* target now either does not exist or is a directory */ } /* return target path */ if (ldest != NULL) afree(ldest, ATEMP); afree(ipath, ATEMP); return (Xclose(xs, xp)); notfound: /* save; freeing memory might trash it */ llen = errno; if (ldest != NULL) afree(ldest, ATEMP); afree(ipath, ATEMP); Xfree(xs, xp); errno = llen; return (NULL); #undef pathlen #undef pathcnd } /** * Makes a filename into result using the following algorithm. * - make result NULL * - if file starts with '/', append file to result & set cdpathp to NULL * - if file starts with ./ or ../ append cwd and file to result * and set cdpathp to NULL * - if the first element of cdpathp doesnt start with a '/' xx or '.' xx * then cwd is appended to result. * - the first element of cdpathp is appended to result * - file is appended to result * - cdpathp is set to the start of the next element in cdpathp (or NULL * if there are no more elements. * The return value indicates whether a non-null element from cdpathp * was appended to result. */ static int make_path(const char *cwd, const char *file, /* pointer to colon-separated list */ char **cdpathp, XString *xsp, int *phys_pathp) { int rval = 0; bool use_cdpath = true; char *plist; size_t len, plen = 0; char *xp = Xstring(*xsp, xp); if (!file) file = null; if (file[0] == '/') { *phys_pathp = 0; use_cdpath = false; } else { if (file[0] == '.') { char c = file[1]; if (c == '.') c = file[2]; if (c == '/' || c == '\0') use_cdpath = false; } plist = *cdpathp; if (!plist) use_cdpath = false; else if (use_cdpath) { char *pend; for (pend = plist; *pend && *pend != ':'; pend++) ; plen = pend - plist; *cdpathp = *pend ? pend + 1 : NULL; } if ((!use_cdpath || !plen || plist[0] != '/') && (cwd && *cwd)) { len = strlen(cwd); XcheckN(*xsp, xp, len); memcpy(xp, cwd, len); xp += len; if (cwd[len - 1] != '/') Xput(*xsp, xp, '/'); } *phys_pathp = Xlength(*xsp, xp); if (use_cdpath && plen) { XcheckN(*xsp, xp, plen); memcpy(xp, plist, plen); xp += plen; if (plist[plen - 1] != '/') Xput(*xsp, xp, '/'); rval = 1; } } len = strlen(file) + 1; XcheckN(*xsp, xp, len); memcpy(xp, file, len); if (!use_cdpath) *cdpathp = NULL; return (rval); } /*- * Simplify pathnames containing "." and ".." entries. * * simplify_path(this) = that * /a/b/c/./../d/.. /a/b * //./C/foo/bar/../baz //C/foo/baz * /foo/ /foo * /foo/../../bar /bar * /foo/./blah/.. /foo * . . * .. .. * ./foo foo * foo/../../../bar ../../bar */ void simplify_path(char *p) { char *dp, *ip, *sp, *tp; size_t len; bool needslash; switch (*p) { case 0: return; case '/': /* exactly two leading slashes? (SUSv4 3.266) */ if (p[1] == '/' && p[2] != '/') /* keep them, e.g. for UNC pathnames */ ++p; needslash = true; break; default: needslash = false; } dp = ip = sp = p; while (*ip) { /* skip slashes in input */ while (*ip == '/') ++ip; if (!*ip) break; /* get next pathname component from input */ tp = ip; while (*ip && *ip != '/') ++ip; len = ip - tp; /* check input for "." and ".." */ if (tp[0] == '.') { if (len == 1) /* just continue with the next one */ continue; else if (len == 2 && tp[1] == '.') { /* parent level, but how? */ if (*p == '/') /* absolute path, only one way */ goto strip_last_component; else if (dp > sp) { /* relative path, with subpaths */ needslash = false; strip_last_component: /* strip off last pathname component */ while (dp > sp) if (*--dp == '/') break; } else { /* relative path, at its beginning */ if (needslash) /* or already dotdot-slash'd */ *dp++ = '/'; /* keep dotdot-slash if not absolute */ *dp++ = '.'; *dp++ = '.'; needslash = true; sp = dp; } /* then continue with the next one */ continue; } } if (needslash) *dp++ = '/'; /* append next pathname component to output */ memmove(dp, tp, len); dp += len; /* append slash if we continue */ needslash = true; /* try next component */ } if (dp == p) /* empty path -> dot */ *dp++ = needslash ? '/' : '.'; *dp = '\0'; } void set_current_wd(const char *nwd) { char *allocd = NULL; if (nwd == NULL) { allocd = ksh_get_wd(); nwd = allocd ? allocd : null; } afree(current_wd, APERM); strdupx(current_wd, nwd, APERM); afree(allocd, ATEMP); } int c_cd(const char **wp) { int optc, rv, phys_path; bool physical = tobool(Flag(FPHYSICAL)); /* was a node from cdpath added in? */ int cdnode; /* show where we went?, error for $PWD */ bool printpath = false, eflag = false; struct tbl *pwd_s, *oldpwd_s; XString xs; char *dir, *allocd = NULL, *tryp, *pwd, *cdpath; while ((optc = ksh_getopt(wp, &builtin_opt, "eLP")) != -1) switch (optc) { case 'e': eflag = true; break; case 'L': physical = false; break; case 'P': physical = true; break; case '?': return (2); } wp += builtin_opt.optind; if (Flag(FRESTRICTED)) { bi_errorf("restricted shell - can't cd"); return (2); } pwd_s = global("PWD"); oldpwd_s = global("OLDPWD"); if (!wp[0]) { /* No arguments - go home */ if ((dir = str_val(global("HOME"))) == null) { bi_errorf("no home directory (HOME not set)"); return (2); } } else if (!wp[1]) { /* One argument: - or dir */ strdupx(allocd, wp[0], ATEMP); if (ksh_isdash((dir = allocd))) { afree(allocd, ATEMP); allocd = NULL; dir = str_val(oldpwd_s); if (dir == null) { bi_errorf("no OLDPWD"); return (2); } printpath = true; } } else if (!wp[2]) { /* Two arguments - substitute arg1 in PWD for arg2 */ size_t ilen, olen, nlen, elen; char *cp; if (!current_wd[0]) { bi_errorf("can't determine current directory"); return (2); } /* * substitute arg1 for arg2 in current path. * if the first substitution fails because the cd fails * we could try to find another substitution. For now * we don't */ if ((cp = strstr(current_wd, wp[0])) == NULL) { bi_errorf("bad substitution"); return (2); } /*- * ilen = part of current_wd before wp[0] * elen = part of current_wd after wp[0] * because current_wd and wp[1] need to be in memory at the * same time beforehand the addition can stay unchecked */ ilen = cp - current_wd; olen = strlen(wp[0]); nlen = strlen(wp[1]); elen = strlen(current_wd + ilen + olen) + 1; dir = allocd = alloc(ilen + nlen + elen, ATEMP); memcpy(dir, current_wd, ilen); memcpy(dir + ilen, wp[1], nlen); memcpy(dir + ilen + nlen, current_wd + ilen + olen, elen); printpath = true; } else { bi_errorf("too many arguments"); return (2); } #ifdef NO_PATH_MAX /* only a first guess; make_path will enlarge xs if necessary */ XinitN(xs, 1024, ATEMP); #else XinitN(xs, PATH_MAX, ATEMP); #endif cdpath = str_val(global("CDPATH")); do { cdnode = make_path(current_wd, dir, &cdpath, &xs, &phys_path); if (physical) rv = chdir(tryp = Xstring(xs, xp) + phys_path); else { simplify_path(Xstring(xs, xp)); rv = chdir(tryp = Xstring(xs, xp)); } } while (rv < 0 && cdpath != NULL); if (rv < 0) { if (cdnode) bi_errorf("%s: %s", dir, "bad directory"); else bi_errorf("%s: %s", tryp, strerror(errno)); afree(allocd, ATEMP); Xfree(xs, xp); return (2); } rv = 0; /* allocd (above) => dir, which is no longer used */ afree(allocd, ATEMP); allocd = NULL; /* Clear out tracked aliases with relative paths */ flushcom(false); /* * Set OLDPWD (note: unsetting OLDPWD does not disable this * setting in AT&T ksh) */ if (current_wd[0]) /* Ignore failure (happens if readonly or integer) */ setstr(oldpwd_s, current_wd, KSH_RETURN_ERROR); if (Xstring(xs, xp)[0] != '/') { pwd = NULL; } else if (!physical) { goto norealpath_PWD; } else if ((pwd = allocd = do_realpath(Xstring(xs, xp))) == NULL) { if (eflag) rv = 1; norealpath_PWD: pwd = Xstring(xs, xp); } /* Set PWD */ if (pwd) { char *ptmp = pwd; set_current_wd(ptmp); /* Ignore failure (happens if readonly or integer) */ setstr(pwd_s, ptmp, KSH_RETURN_ERROR); } else { set_current_wd(null); pwd = Xstring(xs, xp); /* XXX unset $PWD? */ if (eflag) rv = 1; } if (printpath || cdnode) shprintf("%s\n", pwd); afree(allocd, ATEMP); Xfree(xs, xp); return (rv); } #ifdef TIOCSCTTY extern void chvt_reinit(void); static void chvt(const char *fn) { char dv[20]; struct stat sb; int fd; if (*fn == '-') { memcpy(dv, "-/dev/null", sizeof("-/dev/null")); fn = dv + 1; } else { if (stat(fn, &sb)) { memcpy(dv, "/dev/ttyC", 9); strlcpy(dv + 9, fn, sizeof(dv) - 9); if (stat(dv, &sb)) { strlcpy(dv + 8, fn, sizeof(dv) - 8); if (stat(dv, &sb)) errorf("%s: %s %s", "chvt", "can't find tty", fn); } fn = dv; } if (!(sb.st_mode & S_IFCHR)) errorf("%s %s %s", "chvt: not a char", "device", fn); if ((sb.st_uid != 0) && chown(fn, 0, 0)) warningf(false, "%s: %s %s", "chvt", "can't chown root", fn); if (((sb.st_mode & 07777) != 0600) && chmod(fn, (mode_t)0600)) warningf(false, "%s: %s %s", "chvt", "can't chmod 0600", fn); #if HAVE_REVOKE if (revoke(fn)) #endif warningf(false, "%s: %s %s", "chvt", "new shell is potentially insecure, can't revoke", fn); } if ((fd = open(fn, O_RDWR)) == -1) { sleep(1); if ((fd = open(fn, O_RDWR)) == -1) errorf("%s: %s %s", "chvt", "can't open", fn); } switch (fork()) { case -1: errorf("%s: %s %s", "chvt", "fork", "failed"); case 0: break; default: exit(0); } if (setsid() == -1) errorf("%s: %s %s", "chvt", "setsid", "failed"); if (fn != dv + 1) { if (ioctl(fd, TIOCSCTTY, NULL) == -1) errorf("%s: %s %s", "chvt", "TIOCSCTTY", "failed"); if (tcflush(fd, TCIOFLUSH)) errorf("%s: %s %s", "chvt", "TCIOFLUSH", "failed"); } ksh_dup2(fd, 0, false); ksh_dup2(fd, 1, false); ksh_dup2(fd, 2, false); if (fd > 2) close(fd); { register uint32_t h; NZATInit(h); NZATUpdateMem(h, &rndsetupstate, sizeof(rndsetupstate)); NZAATFinish(h); rndset((long)h); } chvt_reinit(); } #endif #ifdef DEBUG char * strchr(char *p, int ch) { for (;; ++p) { if (*p == ch) return (p); if (!*p) return (NULL); } /* NOTREACHED */ } char * strstr(char *b, const char *l) { char first, c; size_t n; if ((first = *l++) == '\0') return (b); n = strlen(l); strstr_look: while ((c = *b++) != first) if (c == '\0') return (NULL); if (strncmp(b, l, n)) goto strstr_look; return (b - 1); } #endif #if !HAVE_STRCASESTR const char * stristr(const char *b, const char *l) { char first, c; size_t n; if ((first = *l++), ((first = ksh_tolower(first)) == '\0')) return (b); n = strlen(l); stristr_look: while ((c = *b++), ((c = ksh_tolower(c)) != first)) if (c == '\0') return (NULL); if (strncasecmp(b, l, n)) goto stristr_look; return (b - 1); } #endif #ifdef MKSH_SMALL char * strndup_i(const char *src, size_t len, Area *ap) { char *dst = NULL; if (src != NULL) { dst = alloc(len + 1, ap); memcpy(dst, src, len); dst[len] = '\0'; } return (dst); } char * strdup_i(const char *src, Area *ap) { return (src == NULL ? NULL : strndup_i(src, strlen(src), ap)); } #endif #if !HAVE_GETRUSAGE #define INVTCK(r,t) do { \ r.tv_usec = ((t) % (1000000 / CLK_TCK)) * (1000000 / CLK_TCK); \ r.tv_sec = (t) / CLK_TCK; \ } while (/* CONSTCOND */ 0) int getrusage(int what, struct rusage *ru) { struct tms tms; clock_t u, s; if (/* ru == NULL || */ times(&tms) == (clock_t)-1) return (-1); switch (what) { case RUSAGE_SELF: u = tms.tms_utime; s = tms.tms_stime; break; case RUSAGE_CHILDREN: u = tms.tms_cutime; s = tms.tms_cstime; break; default: errno = EINVAL; return (-1); } INVTCK(ru->ru_utime, u); INVTCK(ru->ru_stime, s); return (0); } #endif /* * process the string available via fg (get a char) * and fp (put back a char) for backslash escapes, * assuming the first call to *fg gets the char di- * rectly after the backslash; return the character * (0..0xFF), Unicode (wc + 0x100), or -1 if no known * escape sequence was found */ int unbksl(bool cstyle, int (*fg)(void), void (*fp)(int)) { int wc, i, c, fc; fc = (*fg)(); switch (fc) { case 'a': /* * according to the comments in pdksh, \007 seems * to be more portable than \a (due to HP-UX cc, * Ultrix cc, old pcc, etc.) so we avoid the escape * sequence altogether in mksh and assume ASCII */ wc = 7; break; case 'b': wc = '\b'; break; case 'c': if (!cstyle) goto unknown_escape; c = (*fg)(); wc = CTRL(c); break; case 'E': case 'e': wc = 033; break; case 'f': wc = '\f'; break; case 'n': wc = '\n'; break; case 'r': wc = '\r'; break; case 't': wc = '\t'; break; case 'v': /* assume ASCII here as well */ wc = 11; break; case '1': case '2': case '3': case '4': case '5': case '6': case '7': if (!cstyle) goto unknown_escape; /* FALLTHROUGH */ case '0': if (cstyle) (*fp)(fc); /* * look for an octal number with up to three * digits, not counting the leading zero; * convert it to a raw octet */ wc = 0; i = 3; while (i--) if ((c = (*fg)()) >= '0' && c <= '7') wc = (wc << 3) + (c - '0'); else { (*fp)(c); break; } break; case 'U': i = 8; if (/* CONSTCOND */ 0) /* FALLTHROUGH */ case 'u': i = 4; if (/* CONSTCOND */ 0) /* FALLTHROUGH */ case 'x': i = cstyle ? -1 : 2; /** * x: look for a hexadecimal number with up to * two (C style: arbitrary) digits; convert * to raw octet (C style: Unicode if >0xFF) * u/U: look for a hexadecimal number with up to * four (U: eight) digits; convert to Unicode */ wc = 0; while (i--) { wc <<= 4; if ((c = (*fg)()) >= '0' && c <= '9') wc += c - '0'; else if (c >= 'A' && c <= 'F') wc += c - 'A' + 10; else if (c >= 'a' && c <= 'f') wc += c - 'a' + 10; else { wc >>= 4; (*fp)(c); break; } } if ((cstyle && wc > 0xFF) || fc != 'x') /* Unicode marker */ wc += 0x100; break; case '\'': if (!cstyle) goto unknown_escape; wc = '\''; break; case '\\': wc = '\\'; break; default: unknown_escape: (*fp)(fc); return (-1); } return (wc); }