/* $OpenBSD: var.c,v 1.34 2007/10/15 02:16:35 deraadt Exp $ */ /*- * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009 * 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" __RCSID("$MirOS: src/bin/mksh/var.c,v 1.100 2009/12/05 17:43:50 tg Exp $"); /* * Variables * * WARNING: unreadable code, needs a rewrite * * if (flag&INTEGER), val.i contains integer value, and type contains base. * otherwise, (val.s + type) contains string value. * if (flag&EXPORT), val.s contains "name=value" for E-Z exporting. */ static struct tbl vtemp; static struct table specials; static char *formatstr(struct tbl *, const char *); static void export(struct tbl *, const char *); static int special(const char *); static void unspecial(const char *); static void getspec(struct tbl *); static void setspec(struct tbl *); static void unsetspec(struct tbl *); static int getint(struct tbl *, mksh_ari_t *, bool); static mksh_ari_t intval(struct tbl *); static struct tbl *arraysearch(struct tbl *, uint32_t); static const char *array_index_calc(const char *, bool *, uint32_t *); #if !HAVE_ARC4RANDOM static uint32_t oaathash_update(register uint32_t, register const uint8_t *, register size_t); static uint32_t lcg_state = 5381; #endif uint8_t set_refflag = 0; /* * create a new block for function calls and simple commands * assume caller has allocated and set up e->loc */ void newblock(void) { struct block *l; static const char *empty[] = { null }; l = alloc(sizeof(struct block), ATEMP); l->flags = 0; ainit(&l->area); /* todo: could use e->area (l->area => l->areap) */ if (!e->loc) { l->argc = 0; l->argv = empty; } else { l->argc = e->loc->argc; l->argv = e->loc->argv; } l->exit = l->error = NULL; ktinit(&l->vars, &l->area, 0); ktinit(&l->funs, &l->area, 0); l->next = e->loc; e->loc = l; } /* * pop a block handling special variables */ void popblock(void) { struct block *l = e->loc; struct tbl *vp, **vpp = l->vars.tbls, *vq; int i; e->loc = l->next; /* pop block */ for (i = l->vars.size; --i >= 0; ) if ((vp = *vpp++) != NULL && (vp->flag&SPECIAL)) { if ((vq = global(vp->name))->flag & ISSET) setspec(vq); else unsetspec(vq); } if (l->flags & BF_DOGETOPTS) user_opt = l->getopts_state; afreeall(&l->area); afree(l, ATEMP); } /* called by main() to initialise variable data structures */ #define VARSPEC_DEFNS #include "var_spec.h" enum var_specs { #define VARSPEC_ENUMS #include "var_spec.h" V_MAX }; static const char * const initvar_names[] = { #define VARSPEC_ITEMS #include "var_spec.h" }; void initvar(void) { int i = 0; struct tbl *tp; ktinit(&specials, APERM, /* must be 80% of 2^n (currently 12 specials) */ 16); while (i < V_MAX - 1) { tp = ktenter(&specials, initvar_names[i], hash(initvar_names[i])); tp->flag = DEFINED|ISSET; tp->type = ++i; } } /* Used to calculate an array index for global()/local(). Sets *arrayp to * true if this is an array, sets *valp to the array index, returns * the basename of the array. */ static const char * array_index_calc(const char *n, bool *arrayp, uint32_t *valp) { const char *p; int len; char *ap = NULL; *arrayp = false; redo_from_ref: p = skip_varname(n, false); if (!set_refflag && (p != n) && ksh_isalphx(n[0])) { struct block *l = e->loc; struct tbl *vp; char *vn; uint32_t h; strndupx(vn, n, p - n, ATEMP); h = hash(vn); /* check if this is a reference */ do { vp = ktsearch(&l->vars, vn, h); } while (!vp && (l = l->next)); afree(vn, ATEMP); if (vp && (vp->flag & (DEFINED|ASSOC|ARRAY)) == (DEFINED|ASSOC)) { char *cp; /* gotcha! */ cp = shf_smprintf("%s%s", str_val(vp), p); afree(ap, ATEMP); n = ap = cp; goto redo_from_ref; } } if (p != n && *p == '[' && (len = array_ref_len(p))) { char *sub, *tmp; mksh_ari_t rval; /* Calculate the value of the subscript */ *arrayp = true; strndupx(tmp, p + 1, len - 2, ATEMP); sub = substitute(tmp, 0); afree(tmp, ATEMP); strndupx(n, n, p - n, ATEMP); evaluate(sub, &rval, KSH_UNWIND_ERROR, true); *valp = (uint32_t)rval; afree(sub, ATEMP); } return (n); } /* * Search for variable, if not found create globally. */ struct tbl * global(const char *n) { struct block *l = e->loc; struct tbl *vp; int c; bool array; uint32_t h, val; /* Check to see if this is an array */ n = array_index_calc(n, &array, &val); h = hash(n); c = n[0]; if (!ksh_isalphx(c)) { if (array) errorf("bad substitution"); vp = &vtemp; vp->flag = DEFINED; vp->type = 0; vp->areap = ATEMP; *vp->name = c; if (ksh_isdigit(c)) { for (c = 0; ksh_isdigit(*n); n++) c = c*10 + *n-'0'; if (c <= l->argc) /* setstr can't fail here */ setstr(vp, l->argv[c], KSH_RETURN_ERROR); vp->flag |= RDONLY; return (vp); } vp->flag |= RDONLY; if (n[1] != '\0') return (vp); vp->flag |= ISSET|INTEGER; switch (c) { case '$': vp->val.i = kshpid; break; case '!': /* If no job, expand to nothing */ if ((vp->val.i = j_async()) == 0) vp->flag &= ~(ISSET|INTEGER); break; case '?': vp->val.i = exstat; break; case '#': vp->val.i = l->argc; break; case '-': vp->flag &= ~INTEGER; vp->val.s = getoptions(); break; default: vp->flag &= ~(ISSET|INTEGER); } return (vp); } for (l = e->loc; ; l = l->next) { vp = ktsearch(&l->vars, n, h); if (vp != NULL) { if (array) return (arraysearch(vp, val)); else return (vp); } if (l->next == NULL) break; } vp = ktenter(&l->vars, n, h); if (array) vp = arraysearch(vp, val); vp->flag |= DEFINED; if (special(n)) vp->flag |= SPECIAL; return (vp); } /* * Search for local variable, if not found create locally. */ struct tbl * local(const char *n, bool copy) { struct block *l = e->loc; struct tbl *vp; bool array; uint32_t h, val; /* Check to see if this is an array */ n = array_index_calc(n, &array, &val); h = hash(n); if (!ksh_isalphx(*n)) { vp = &vtemp; vp->flag = DEFINED|RDONLY; vp->type = 0; vp->areap = ATEMP; return (vp); } vp = ktenter(&l->vars, n, h); if (copy && !(vp->flag & DEFINED)) { struct block *ll = l; struct tbl *vq = NULL; while ((ll = ll->next) && !(vq = ktsearch(&ll->vars, n, h))) ; if (vq) { vp->flag |= vq->flag & (EXPORT | INTEGER | RDONLY | LJUST | RJUST | ZEROFIL | LCASEV | UCASEV_AL | INT_U | INT_L); if (vq->flag & INTEGER) vp->type = vq->type; vp->u2.field = vq->u2.field; } } if (array) vp = arraysearch(vp, val); vp->flag |= DEFINED; if (special(n)) vp->flag |= SPECIAL; return (vp); } /* get variable string value */ char * str_val(struct tbl *vp) { char *s; if ((vp->flag&SPECIAL)) getspec(vp); if (!(vp->flag&ISSET)) s = null; /* special to dollar() */ else if (!(vp->flag&INTEGER)) /* string source */ s = vp->val.s + vp->type; else { /* integer source */ /* worst case number length is when base=2 */ /* 1 (minus) + 2 (base, up to 36) + 1 ('#') + number of bits * in the mksh_uari_t + 1 (NUL) */ char strbuf[1 + 2 + 1 + 8 * sizeof(mksh_uari_t) + 1]; const char *digits = (vp->flag & UCASEV_AL) ? digits_uc : digits_lc; mksh_uari_t n; int base; s = strbuf + sizeof(strbuf); if (vp->flag & INT_U) n = vp->val.u; else n = (vp->val.i < 0) ? -vp->val.i : vp->val.i; base = (vp->type == 0) ? 10 : vp->type; if (base == 1) { size_t sz = 1; *(s = strbuf) = '1'; s[1] = '#'; if (!UTFMODE || ((n & 0xFF80) == 0xEF80)) /* OPTU-16 -> raw octet */ s[2] = n & 0xFF; else sz = utf_wctomb(s + 2, n); s[2 + sz] = '\0'; } else { *--s = '\0'; do { *--s = digits[n % base]; n /= base; } while (n != 0); if (base != 10) { *--s = '#'; *--s = digits[base % 10]; if (base >= 10) *--s = digits[base / 10]; } if (!(vp->flag & INT_U) && vp->val.i < 0) *--s = '-'; } if (vp->flag & (RJUST|LJUST)) /* case already dealt with */ s = formatstr(vp, s); else strdupx(s, s, ATEMP); } return (s); } /* get variable integer value, with error checking */ static mksh_ari_t intval(struct tbl *vp) { mksh_ari_t num; int base; base = getint(vp, &num, false); if (base == -1) /* XXX check calls - is error here ok by POSIX? */ errorf("%s: bad number", str_val(vp)); return (num); } /* set variable to string value */ int setstr(struct tbl *vq, const char *s, int error_ok) { char *salloc = NULL; int no_ro_check = error_ok & 0x4; error_ok &= ~0x4; if ((vq->flag & RDONLY) && !no_ro_check) { warningf(true, "%s: is read only", vq->name); if (!error_ok) errorfz(); return (0); } if (!(vq->flag&INTEGER)) { /* string dest */ if ((vq->flag&ALLOC)) { /* debugging */ if (s >= vq->val.s && s <= vq->val.s + strlen(vq->val.s)) internal_errorf( "setstr: %s=%s: assigning to self", vq->name, s); afree(vq->val.s, vq->areap); } vq->flag &= ~(ISSET|ALLOC); vq->type = 0; if (s && (vq->flag & (UCASEV_AL|LCASEV|LJUST|RJUST))) s = salloc = formatstr(vq, s); if ((vq->flag&EXPORT)) export(vq, s); else { strdupx(vq->val.s, s, vq->areap); vq->flag |= ALLOC; } } else { /* integer dest */ if (!v_evaluate(vq, s, error_ok, true)) return (0); } vq->flag |= ISSET; if ((vq->flag&SPECIAL)) setspec(vq); afree(salloc, ATEMP); return (1); } /* set variable to integer */ void setint(struct tbl *vq, mksh_ari_t n) { if (!(vq->flag&INTEGER)) { struct tbl *vp = &vtemp; vp->flag = (ISSET|INTEGER); vp->type = 0; vp->areap = ATEMP; vp->val.i = n; /* setstr can't fail here */ setstr(vq, str_val(vp), KSH_RETURN_ERROR); } else vq->val.i = n; vq->flag |= ISSET; if ((vq->flag&SPECIAL)) setspec(vq); } static int getint(struct tbl *vp, mksh_ari_t *nump, bool arith) { char *s; int c, base, neg; bool have_base = false; mksh_ari_t num; if (vp->flag&SPECIAL) getspec(vp); /* XXX is it possible for ISSET to be set and val.s to be 0? */ if (!(vp->flag&ISSET) || (!(vp->flag&INTEGER) && vp->val.s == NULL)) return (-1); if (vp->flag&INTEGER) { *nump = vp->val.i; return (vp->type); } s = vp->val.s + vp->type; if (s == NULL) /* redundant given initial test */ s = null; base = 10; num = 0; neg = 0; if (arith && *s == '0' && *(s+1)) { s++; if (*s == 'x' || *s == 'X') { s++; base = 16; } else if (vp->flag & ZEROFIL) { while (*s == '0') s++; } else base = 8; have_base = true; } for (c = *s++; c ; c = *s++) { if (c == '-') { neg++; continue; } else if (c == '#') { base = (int)num; if (have_base || base < 1 || base > 36) return (-1); if (base == 1) { unsigned int wc; if (!UTFMODE) wc = *(unsigned char *)s; else if (utf_mbtowc(&wc, s) == (size_t)-1) /* OPTU-8 -> OPTU-16 */ /* * (with a twist: 1#\uEF80 converts * the same as 1#\x80 does, thus is * not round-tripping correctly XXX) */ wc = 0xEF00 + *(unsigned char *)s; *nump = (mksh_ari_t)wc; return (1); } num = 0; have_base = true; continue; } else if (ksh_isdigit(c)) c -= '0'; else if (ksh_islower(c)) c -= 'a' - 10; else if (ksh_isupper(c)) c -= 'A' - 10; else return (-1); if (c < 0 || c >= base) return (-1); num = num * base + c; } if (neg) num = -num; *nump = num; return (base); } /* convert variable vq to integer variable, setting its value from vp * (vq and vp may be the same) */ struct tbl * setint_v(struct tbl *vq, struct tbl *vp, bool arith) { int base; mksh_ari_t num; if ((base = getint(vp, &num, arith)) == -1) return (NULL); if (!(vq->flag & INTEGER) && (vq->flag & ALLOC)) { vq->flag &= ~ALLOC; afree(vq->val.s, vq->areap); } vq->val.i = num; if (vq->type == 0) /* default base */ vq->type = base; vq->flag |= ISSET|INTEGER; if (vq->flag&SPECIAL) setspec(vq); return (vq); } static char * formatstr(struct tbl *vp, const char *s) { int olen, nlen; char *p, *q; size_t psiz; olen = utf_mbswidth(s); if (vp->flag & (RJUST|LJUST)) { if (!vp->u2.field) /* default field width */ vp->u2.field = olen; nlen = vp->u2.field; } else nlen = olen; p = alloc((psiz = nlen * /* MB_LEN_MAX */ 3 + 1), ATEMP); if (vp->flag & (RJUST|LJUST)) { int slen = olen, i = 0; if (vp->flag & RJUST) { const char *qq = s; int n = 0; while (i < slen) i += utf_widthadj(qq, &qq); /* strip trailing spaces (AT&T uses qq[-1] == ' ') */ while (qq > s && ksh_isspace(qq[-1])) { --qq; --slen; } if (vp->flag & ZEROFIL && vp->flag & INTEGER) { if (s[1] == '#') n = 2; else if (s[2] == '#') n = 3; if (vp->u2.field <= n) n = 0; } if (n) { memcpy(p, s, n); s += n; } while (slen > vp->u2.field) slen -= utf_widthadj(s, &s); if (vp->u2.field - slen) memset(p + n, (vp->flag & ZEROFIL) ? '0' : ' ', vp->u2.field - slen); slen -= n; shf_snprintf(p + vp->u2.field - slen, psiz - (vp->u2.field - slen), "%.*s", slen, s); } else { /* strip leading spaces/zeros */ while (ksh_isspace(*s)) s++; if (vp->flag & ZEROFIL) while (*s == '0') s++; shf_snprintf(p, nlen + 1, "%-*.*s", vp->u2.field, vp->u2.field, s); } } else memcpy(p, s, strlen(s) + 1); if (vp->flag & UCASEV_AL) { for (q = p; *q; q++) *q = ksh_toupper(*q); } else if (vp->flag & LCASEV) { for (q = p; *q; q++) *q = ksh_tolower(*q); } return (p); } /* * make vp->val.s be "name=value" for quick exporting. */ static void export(struct tbl *vp, const char *val) { char *xp; char *op = (vp->flag&ALLOC) ? vp->val.s : NULL; int namelen = strlen(vp->name); int vallen = strlen(val) + 1; vp->flag |= ALLOC; xp = alloc(namelen + 1 + vallen, vp->areap); memcpy(vp->val.s = xp, vp->name, namelen); xp += namelen; *xp++ = '='; vp->type = xp - vp->val.s; /* offset to value */ memcpy(xp, val, vallen); if (op != NULL) afree(op, vp->areap); } /* * lookup variable (according to (set&LOCAL)), * set its attributes (INTEGER, RDONLY, EXPORT, TRACE, LJUST, RJUST, ZEROFIL, * LCASEV, UCASEV_AL), and optionally set its value if an assignment. */ struct tbl * typeset(const char *var, Tflag set, Tflag clr, int field, int base) { struct tbl *vp; struct tbl *vpbase, *t; char *tvar; const char *val; /* check for valid variable name, search for value */ val = skip_varname(var, false); if (val == var) return (NULL); if (*val == '[') { int len; if (set_refflag) errorf("%s: reference variable cannot be an array", var); len = array_ref_len(val); if (len == 0) return (NULL); /* IMPORT is only used when the shell starts up and is * setting up its environment. Allow only simple array * references at this time since parameter/command substitution * is preformed on the [expression] which would be a major * security hole. */ if (set & IMPORT) { int i; for (i = 1; i < len - 1; i++) if (!ksh_isdigit(val[i])) return (NULL); } val += len; } if (*val == '=') strndupx(tvar, var, val++ - var, ATEMP); else { /* Importing from original environment: must have an = */ if (set & IMPORT) return (NULL); strdupx(tvar, var, ATEMP); val = NULL; } /* Prevent typeset from creating a local PATH/ENV/SHELL */ if (Flag(FRESTRICTED) && (strcmp(tvar, "PATH") == 0 || strcmp(tvar, "ENV") == 0 || strcmp(tvar, "SHELL") == 0)) errorf("%s: restricted", tvar); vp = (set&LOCAL) ? local(tvar, (set & LOCAL_COPY) ? true : false) : global(tvar); if (set_refflag == 2 && (vp->flag & (ARRAY|ASSOC)) == ASSOC) vp->flag &= ~ASSOC; else if (set_refflag == 1) { if (vp->flag & ARRAY) { struct tbl *a, *tmp; /* Free up entire array */ for (a = vp->u.array; a; ) { tmp = a; a = a->u.array; if (tmp->flag & ALLOC) afree(tmp->val.s, tmp->areap); afree(tmp, tmp->areap); } vp->u.array = NULL; vp->flag &= ~ARRAY; } vp->flag |= ASSOC; } set &= ~(LOCAL|LOCAL_COPY); vpbase = (vp->flag & ARRAY) ? global(arrayname(var)) : vp; /* only allow export flag to be set. AT&T ksh allows any attribute to * be changed which means it can be truncated or modified (-L/-R/-Z/-i) */ if ((vpbase->flag&RDONLY) && (val || clr || (set & ~EXPORT))) /* XXX check calls - is error here ok by POSIX? */ errorf("%s: is read only", tvar); afree(tvar, ATEMP); /* most calls are with set/clr == 0 */ if (set | clr) { int ok = 1; /* XXX if x[0] isn't set, there will be problems: need to have * one copy of attributes for arrays... */ for (t = vpbase; t; t = t->u.array) { int fake_assign; char *s = NULL; char *free_me = NULL; fake_assign = (t->flag & ISSET) && (!val || t != vp) && ((set & (UCASEV_AL|LCASEV|LJUST|RJUST|ZEROFIL)) || ((t->flag & INTEGER) && (clr & INTEGER)) || (!(t->flag & INTEGER) && (set & INTEGER))); if (fake_assign) { if (t->flag & INTEGER) { s = str_val(t); free_me = NULL; } else { s = t->val.s + t->type; free_me = (t->flag & ALLOC) ? t->val.s : NULL; } t->flag &= ~ALLOC; } if (!(t->flag & INTEGER) && (set & INTEGER)) { t->type = 0; t->flag &= ~ALLOC; } t->flag = (t->flag | set) & ~clr; /* Don't change base if assignment is to be done, * in case assignment fails. */ if ((set & INTEGER) && base > 0 && (!val || t != vp)) t->type = base; if (set & (LJUST|RJUST|ZEROFIL)) t->u2.field = field; if (fake_assign) { if (!setstr(t, s, KSH_RETURN_ERROR)) { /* Somewhat arbitrary action here: * zap contents of variable, but keep * the flag settings. */ ok = 0; if (t->flag & INTEGER) t->flag &= ~ISSET; else { if (t->flag & ALLOC) afree(t->val.s, t->areap); t->flag &= ~(ISSET|ALLOC); t->type = 0; } } if (free_me) afree(free_me, t->areap); } } if (!ok) errorfz(); } if (val != NULL) { if (vp->flag&INTEGER) { /* do not zero base before assignment */ setstr(vp, val, KSH_UNWIND_ERROR | 0x4); /* Done after assignment to override default */ if (base > 0) vp->type = base; } else /* setstr can't fail (readonly check already done) */ setstr(vp, val, KSH_RETURN_ERROR | 0x4); } /* only x[0] is ever exported, so use vpbase */ if ((vpbase->flag&EXPORT) && !(vpbase->flag&INTEGER) && vpbase->type == 0) export(vpbase, (vpbase->flag&ISSET) ? vpbase->val.s : null); return (vp); } /* Unset a variable. array_ref is set if there was an array reference in * the name lookup (eg, x[2]). */ void unset(struct tbl *vp, int array_ref) { if (vp->flag & ALLOC) afree(vp->val.s, vp->areap); if ((vp->flag & ARRAY) && !array_ref) { struct tbl *a, *tmp; /* Free up entire array */ for (a = vp->u.array; a; ) { tmp = a; a = a->u.array; if (tmp->flag & ALLOC) afree(tmp->val.s, tmp->areap); afree(tmp, tmp->areap); } vp->u.array = NULL; } /* If foo[0] is being unset, the remainder of the array is kept... */ vp->flag &= SPECIAL | (array_ref ? ARRAY|DEFINED : 0); if (vp->flag & SPECIAL) unsetspec(vp); /* responsible for 'unspecial'ing var */ } /* return a pointer to the first char past a legal variable name (returns the * argument if there is no legal name, returns a pointer to the terminating * NUL if whole string is legal). */ const char * skip_varname(const char *s, int aok) { int alen; if (s && ksh_isalphx(*s)) { while (*++s && ksh_isalnux(*s)) ; if (aok && *s == '[' && (alen = array_ref_len(s))) s += alen; } return (s); } /* Return a pointer to the first character past any legal variable name */ const char * skip_wdvarname(const char *s, int aok) /* skip array de-reference? */ { if (s[0] == CHAR && ksh_isalphx(s[1])) { do { s += 2; } while (s[0] == CHAR && ksh_isalnux(s[1])); if (aok && s[0] == CHAR && s[1] == '[') { /* skip possible array de-reference */ const char *p = s; char c; int depth = 0; while (1) { if (p[0] != CHAR) break; c = p[1]; p += 2; if (c == '[') depth++; else if (c == ']' && --depth == 0) { s = p; break; } } } } return (s); } /* Check if coded string s is a variable name */ int is_wdvarname(const char *s, int aok) { const char *p = skip_wdvarname(s, aok); return (p != s && p[0] == EOS); } /* Check if coded string s is a variable assignment */ int is_wdvarassign(const char *s) { const char *p = skip_wdvarname(s, true); return (p != s && p[0] == CHAR && p[1] == '='); } /* * Make the exported environment from the exported names in the dictionary. */ char ** makenv(void) { struct block *l; XPtrV denv; struct tbl *vp, **vpp; int i; XPinit(denv, 64); for (l = e->loc; l != NULL; l = l->next) for (vpp = l->vars.tbls, i = l->vars.size; --i >= 0; ) if ((vp = *vpp++) != NULL && (vp->flag&(ISSET|EXPORT)) == (ISSET|EXPORT)) { struct block *l2; struct tbl *vp2; uint32_t h = hash(vp->name); /* unexport any redefined instances */ for (l2 = l->next; l2 != NULL; l2 = l2->next) { vp2 = ktsearch(&l2->vars, vp->name, h); if (vp2 != NULL) vp2->flag &= ~EXPORT; } if ((vp->flag&INTEGER)) { /* integer to string */ char *val; val = str_val(vp); vp->flag &= ~(INTEGER|RDONLY|SPECIAL); /* setstr can't fail here */ setstr(vp, val, KSH_RETURN_ERROR); } XPput(denv, vp->val.s); } XPput(denv, NULL); return ((char **)XPclose(denv)); } #if !HAVE_ARC4RANDOM static uint32_t oaathash_update(register uint32_t h, register const uint8_t *cp, register size_t n) { while (n--) { h += *cp++; h += h << 10; h ^= h >> 6; } return (h); } void change_random(const void *vp, size_t n) { register uint32_t h = 0x100; struct { const void *sp, *bp, *dp; size_t dsz; struct timeval tv; uint32_t s; } i; i.dp = vp; i.dsz = n; i.s = lcg_state; i.bp = &lcg_state; i.sp = &i; gettimeofday(&i.tv, NULL); h = oaathash_update(oaathash_update(h, (void *)&i, sizeof(i)), vp, n); /* oaathash_finalise */ h += h << 3; h ^= h >> 11; h += h << 15; lcg_state = h; } #endif /* * handle special variables with side effects - PATH, SECONDS. */ /* Test if name is a special parameter */ static int special(const char *name) { struct tbl *tp; tp = ktsearch(&specials, name, hash(name)); return (tp && (tp->flag & ISSET) ? tp->type : V_NONE); } /* Make a variable non-special */ static void unspecial(const char *name) { struct tbl *tp; tp = ktsearch(&specials, name, hash(name)); if (tp) ktdelete(tp); } static time_t seconds; /* time SECONDS last set */ static int user_lineno; /* what user set $LINENO to */ static void getspec(struct tbl *vp) { register mksh_ari_t i; int st; switch ((st = special(vp->name))) { case V_SECONDS: /* * On start up the value of SECONDS is used before * it has been set - don't do anything in this case * (see initcoms[] in main.c). */ if (vp->flag & ISSET) { struct timeval tv; gettimeofday(&tv, NULL); i = tv.tv_sec - seconds; } else return; break; case V_RANDOM: #if HAVE_ARC4RANDOM i = arc4random() & 0x7FFF; #else /* * this is the same Linear Congruential PRNG as Borland * C/C++ allegedly uses in its built-in rand() function */ i = ((lcg_state = 22695477 * lcg_state + 1) >> 16) & 0x7FFF; #endif break; case V_HISTSIZE: i = histsize; break; case V_OPTIND: i = user_opt.uoptind; break; case V_LINENO: i = current_lineno + user_lineno; break; case V_COLUMNS: case V_LINES: /* * Do NOT export COLUMNS/LINES. Many applications * check COLUMNS/LINES before checking ws.ws_col/row, * so if the app is started with C/L in the environ * and the window is then resized, the app won't * see the change cause the environ doesn't change. */ change_winsz(); i = st == V_COLUMNS ? x_cols : x_lins; break; default: /* do nothing, do not touch vp at all */ return; } vp->flag &= ~SPECIAL; setint(vp, i); vp->flag |= SPECIAL; } static void setspec(struct tbl *vp) { mksh_ari_t i; char *s; int st; switch ((st = special(vp->name))) { case V_PATH: if (path) afree(path, APERM); s = str_val(vp); strdupx(path, s, APERM); flushcom(1); /* clear tracked aliases */ return; case V_IFS: setctypes(s = str_val(vp), C_IFS); ifs0 = *s; return; case V_TMPDIR: if (tmpdir) { afree(tmpdir, APERM); tmpdir = NULL; } /* Use tmpdir iff it is an absolute path, is writable and * searchable and is a directory... */ { struct stat statb; s = str_val(vp); if (s[0] == '/' && access(s, W_OK|X_OK) == 0 && stat(s, &statb) == 0 && S_ISDIR(statb.st_mode)) strdupx(tmpdir, s, APERM); } break; #if HAVE_PERSISTENT_HISTORY case V_HISTFILE: sethistfile(str_val(vp)); break; #endif case V_TMOUT: /* AT&T ksh seems to do this (only listen if integer) */ if (vp->flag & INTEGER) ksh_tmout = vp->val.i >= 0 ? vp->val.i : 0; break; /* common sub-cases */ case V_OPTIND: case V_HISTSIZE: case V_COLUMNS: case V_LINES: case V_RANDOM: case V_SECONDS: case V_LINENO: vp->flag &= ~SPECIAL; i = intval(vp); vp->flag |= SPECIAL; break; default: /* do nothing, do not touch vp at all */ return; } /* process the singular parts of the common cases */ switch (st) { case V_OPTIND: getopts_reset((int)i); break; case V_HISTSIZE: sethistsize((int)i); break; case V_COLUMNS: if (i >= MIN_COLS) x_cols = i; break; case V_LINES: if (i >= MIN_LINS) x_lins = i; break; case V_RANDOM: #if HAVE_ARC4RANDOM #if HAVE_ARC4RANDOM_PUSHB if (Flag(FARC4RANDOM)) /* * things like initialisation, environment import, * etc. are already done */ arc4random_pushb(&i, sizeof(i)); else /* during start-up phase or somesuch */ #endif /* HAVE_ARC4RANDOM_PUSHB */ arc4random_addrandom((void *)&i, sizeof(i)); #else /* !HAVE_ARC4RANDOM */ /* * mksh R40+ no longer has the traditional repeatability * of $RANDOM sequences, but always retains state */ change_random(&i, sizeof(i)); #endif /* !HAVE_ARC4RANDOM */ break; case V_SECONDS: { struct timeval tv; gettimeofday(&tv, NULL); seconds = tv.tv_sec - i; } break; case V_LINENO: /* The -1 is because line numbering starts at 1. */ user_lineno = (unsigned int)i - current_lineno - 1; break; } } static void unsetspec(struct tbl *vp) { switch (special(vp->name)) { case V_PATH: if (path) afree(path, APERM); strdupx(path, def_path, APERM); flushcom(1); /* clear tracked aliases */ break; case V_IFS: setctypes(" \t\n", C_IFS); ifs0 = ' '; break; case V_TMPDIR: /* should not become unspecial */ if (tmpdir) { afree(tmpdir, APERM); tmpdir = NULL; } break; case V_LINENO: case V_RANDOM: case V_SECONDS: case V_TMOUT: /* AT&T ksh leaves previous value in place */ unspecial(vp->name); break; /* AT&T ksh man page says OPTIND, OPTARG and _ lose special meaning, * but OPTARG does not (still set by getopts) and _ is also still * set in various places. * Don't know what AT&T does for: * HISTSIZE, HISTFILE, * Unsetting these in AT&T ksh does not loose the 'specialness': * no effect: IFS, COLUMNS, PATH, TMPDIR */ } } /* * Search for (and possibly create) a table entry starting with * vp, indexed by val. */ static struct tbl * arraysearch(struct tbl *vp, uint32_t val) { struct tbl *prev, *curr, *new; size_t len; vp->flag = (vp->flag | (ARRAY|DEFINED)) & ~ASSOC; /* The table entry is always [0] */ if (val == 0) return (vp); prev = vp; curr = vp->u.array; while (curr && curr->ua.index < val) { prev = curr; curr = curr->u.array; } if (curr && curr->ua.index == val) { if (curr->flag&ISSET) return (curr); new = curr; } else new = NULL; len = strlen(vp->name) + 1; if (!new) { new = alloc(offsetof(struct tbl, name[0]) + len, vp->areap); memcpy(new->name, vp->name, len); } new->flag = (vp->flag & ~(ALLOC|DEFINED|ISSET|SPECIAL)) | AINDEX; new->type = vp->type; new->areap = vp->areap; new->u2.field = vp->u2.field; new->ua.index = val; #ifdef notyet_ktremove /* XXX array indices must not be ktdelete'd, for now */ new->tablep = NULL; #endif if (curr != new) { /* not reusing old array entry */ prev->u.array = new; new->u.array = curr; } return (new); } /* Return the length of an array reference (eg, [1+2]) - cp is assumed * to point to the open bracket. Returns 0 if there is no matching closing * bracket. */ int array_ref_len(const char *cp) { const char *s = cp; int c; int depth = 0; while ((c = *s++) && (c != ']' || --depth)) if (c == '[') depth++; if (!c) return (0); return (s - cp); } /* * Make a copy of the base of an array name */ char * arrayname(const char *str) { const char *p; char *rv; if ((p = cstrchr(str, '[')) == 0) /* Shouldn't happen, but why worry? */ strdupx(rv, str, ATEMP); else strndupx(rv, str, p - str, ATEMP); return (rv); } /* set (or overwrite, if reset) the array variable var to the values in vals */ mksh_uari_t set_array(const char *var, bool reset, const char **vals) { struct tbl *vp, *vq; mksh_uari_t i; const char *ccp; #ifndef MKSH_SMALL char *cp; mksh_uari_t j; #endif /* to get local array, use "typeset foo; set -A foo" */ vp = global(var); /* Note: AT&T ksh allows set -A but not set +A of a read-only var */ if ((vp->flag&RDONLY)) errorf("%s: is read only", var); /* This code is quite non-optimal */ if (reset) /* trash existing values and attributes */ unset(vp, 0); /* todo: would be nice for assignment to completely succeed or * completely fail. Only really effects integer arrays: * evaluation of some of vals[] may fail... */ i = 0; #ifndef MKSH_SMALL j = 0; #else #define j i #endif while ((ccp = vals[i])) { #ifndef MKSH_SMALL if (*ccp == '[') { int level = 0; while (*ccp) { if (*ccp == ']' && --level == 0) break; if (*ccp == '[') ++level; ++ccp; } if (*ccp == ']' && level == 0 && ccp[1] == '=') { strndupx(cp, vals[i] + 1, ccp - (vals[i] + 1), ATEMP); evaluate(substitute(cp, 0), (mksh_ari_t *)&j, KSH_UNWIND_ERROR, true); afree(cp, ATEMP); ccp += 2; } else ccp = vals[i]; } #endif vq = arraysearch(vp, j); /* would be nice to deal with errors here... (see above) */ #if 0 shprintf("setting '%s'[%lu]='%s' <- '%s'\n", vp->name, (unsigned long)j, ccp, vals[i]); #endif setstr(vq, ccp, KSH_RETURN_ERROR); i++; #ifndef MKSH_SMALL j++; #endif } return (i); } void change_winsz(void) { if (x_lins < 0) { /* first time initialisation */ #ifdef TIOCGWINSZ if (tty_fd < 0) /* non-FTALKING, try to get an fd anyway */ tty_init(false, false); #endif x_cols = -1; } #ifdef TIOCGWINSZ /* check if window size has changed since first time */ if (tty_fd >= 0) { struct winsize ws; if (ioctl(tty_fd, TIOCGWINSZ, &ws) >= 0) { if (ws.ws_col) x_cols = ws.ws_col; if (ws.ws_row) x_lins = ws.ws_row; } } #endif /* bounds check for sane values, use defaults otherwise */ if (x_cols < MIN_COLS) x_cols = 80; if (x_lins < MIN_LINS) x_lins = 24; }