/*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Kenneth Almquist. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)var.c 8.3 (Berkeley) 5/4/95 * $FreeBSD: src/bin/sh/var.c,v 1.15.2.2 2002/08/27 01:36:28 tjr Exp $ * $DragonFly: src/bin/sh/var.c,v 1.8 2005/04/19 05:18:19 cpressey Exp $ */ #include #include /* * Shell variables. */ #include #include "shell.h" #include "output.h" #include "expand.h" #include "nodes.h" /* for other headers */ #include "eval.h" /* defines cmdenviron */ #include "exec.h" #include "syntax.h" #include "options.h" #include "mail.h" #include "var.h" #include "memalloc.h" #include "error.h" #include "mystring.h" #include "parser.h" #ifndef NO_HISTORY #include "myhistedit.h" #endif #define VTABSIZE 39 struct varinit { struct var *var; int flags; char *text; void (*func)(const char *); }; #ifndef NO_HISTORY struct var vhistsize; #endif struct var vifs; struct var vmail; struct var vmpath; struct var vpath; struct var vppid; struct var vps1; struct var vps2; struct var vvers; STATIC struct var voptind; STATIC const struct varinit varinit[] = { #ifndef NO_HISTORY { &vhistsize, VSTRFIXED|VTEXTFIXED|VUNSET, "HISTSIZE=", sethistsize }, #endif { &vifs, VSTRFIXED|VTEXTFIXED, "IFS= \t\n", NULL }, { &vmail, VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL=", NULL }, { &vmpath, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH=", NULL }, { &vpath, VSTRFIXED|VTEXTFIXED, "PATH=/bin:/usr/bin", changepath }, { &vppid, VSTRFIXED|VTEXTFIXED|VUNSET, "PPID=", NULL }, /* * vps1 depends on uid */ { &vps2, VSTRFIXED|VTEXTFIXED, "PS2=> ", NULL }, { &voptind, VSTRFIXED|VTEXTFIXED, "OPTIND=1", getoptsreset }, { NULL, 0, NULL, NULL } }; STATIC struct var *vartab[VTABSIZE]; STATIC struct var **hashvar(const char *); STATIC int varequal(const char *, const char *); STATIC int localevar(const char *); /* * Initialize the variable symbol tables and import the environment. */ #ifdef mkinit INCLUDE "var.h" INIT { char **envp; extern char **environ; initvar(); for (envp = environ ; *envp ; envp++) { if (strchr(*envp, '=')) { setvareq(*envp, VEXPORT|VTEXTFIXED); } } } #endif /* * This routine initializes the builtin variables. It is called when the * shell is initialized and again when a shell procedure is spawned. */ void initvar(void) { char ppid[20]; const struct varinit *ip; struct var *vp; struct var **vpp; for (ip = varinit ; (vp = ip->var) != NULL ; ip++) { if ((vp->flags & VEXPORT) == 0) { vpp = hashvar(ip->text); vp->next = *vpp; *vpp = vp; vp->text = ip->text; vp->flags = ip->flags; vp->func = ip->func; } } /* * PS1 depends on uid */ if ((vps1.flags & VEXPORT) == 0) { vpp = hashvar("PS1="); vps1.next = *vpp; *vpp = &vps1; vps1.text = geteuid() ? "PS1=$ " : "PS1=# "; vps1.flags = VSTRFIXED|VTEXTFIXED; } if ((vppid.flags & VEXPORT) == 0) { fmtstr(ppid, sizeof(ppid), "%d", (int)getppid()); setvarsafe("PPID", ppid, 0); } } /* * Safe version of setvar, returns 1 on success 0 on failure. */ int setvarsafe(const char *name, const char *val, int flags) { struct jmploc jmploc; struct jmploc *volatile savehandler = handler; int err = 0; #if __GNUC__ /* Avoid longjmp clobbering */ (void) &err; #endif if (setjmp(jmploc.loc)) err = 1; else { handler = &jmploc; setvar(name, val, flags); } handler = savehandler; return err; } /* * Set the value of a variable. The flags argument is tored with the * flags of the variable. If val is NULL, the variable is unset. */ void setvar(const char *name, const char *val, int flags) { const char *cp; char *p; int len; int namelen; char *nameeq; int isbad; isbad = 0; cp = name; if (!is_name(*cp)) isbad = 1; cp++; for (;;) { if (!is_in_name(*cp)) { if (*cp == '\0' || *cp == '=') break; isbad = 1; } cp++; } namelen = cp - name; if (isbad) error("%.*s: bad variable name", namelen, name); len = namelen + 2; /* 2 is space for '=' and '\0' */ if (val == NULL) { flags |= VUNSET; } else { len += strlen(val); } p = nameeq = ckmalloc(len); cp = name; while (--namelen >= 0) *p++ = *cp++; *p++ = '='; *p = '\0'; if (val) scopy(val, p); setvareq(nameeq, flags); } STATIC int localevar(const char *s) { static const char * const lnames[7] = { "ALL", "COLLATE", "CTYPE", "MONETARY", "NUMERIC", "TIME", NULL }; const char * const *ss; if (*s != 'L') return 0; if (varequal(s + 1, "ANG")) return 1; if (strncmp(s + 1, "C_", 2) != 0) return 0; for (ss = lnames; *ss ; ss++) if (varequal(s + 3, *ss)) return 1; return 0; } /* * Same as setvar except that the variable and value are passed in * the first argument as name=value. Since the first argument will * be actually stored in the table, it should not be a string that * will go away. */ void setvareq(char *s, int flags) { struct var *vp, **vpp; int len; if (aflag) flags |= VEXPORT; vpp = hashvar(s); for (vp = *vpp ; vp ; vp = vp->next) { if (varequal(s, vp->text)) { if (vp->flags & VREADONLY) { len = strchr(s, '=') - s; error("%.*s: is read only", len, s); } INTOFF; if (vp->func && (flags & VNOFUNC) == 0) (*vp->func)(strchr(s, '=') + 1); if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0) ckfree(vp->text); vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET); vp->flags |= flags; vp->text = s; /* * We could roll this to a function, to handle it as * a regular variable function callback, but why bother? */ if (vp == &vmpath || (vp == &vmail && ! mpathset())) chkmail(1); if ((vp->flags & VEXPORT) && localevar(s)) { putenv(s); setlocale(LC_ALL, ""); } INTON; return; } } /* not found */ vp = ckmalloc(sizeof (*vp)); vp->flags = flags; vp->text = s; vp->next = *vpp; vp->func = NULL; INTOFF; *vpp = vp; if ((vp->flags & VEXPORT) && localevar(s)) { putenv(s); setlocale(LC_ALL, ""); } INTON; } /* * Process a linked list of variable assignments. */ void listsetvar(struct strlist *list) { struct strlist *lp; INTOFF; for (lp = list ; lp ; lp = lp->next) { setvareq(savestr(lp->text), 0); } INTON; } /* * Find the value of a variable. Returns NULL if not set. */ char * lookupvar(const char *name) { struct var *v; for (v = *hashvar(name) ; v ; v = v->next) { if (varequal(v->text, name)) { if (v->flags & VUNSET) return NULL; return strchr(v->text, '=') + 1; } } return NULL; } /* * Search the environment of a builtin command. If the second argument * is nonzero, return the value of a variable even if it hasn't been * exported. */ char * bltinlookup(const char *name, int doall) { struct strlist *sp; struct var *v; for (sp = cmdenviron ; sp ; sp = sp->next) { if (varequal(sp->text, name)) return strchr(sp->text, '=') + 1; } for (v = *hashvar(name) ; v ; v = v->next) { if (varequal(v->text, name)) { if ((v->flags & VUNSET) || (!doall && (v->flags & VEXPORT) == 0)) return NULL; return strchr(v->text, '=') + 1; } } return NULL; } /* * Generate a list of exported variables. This routine is used to construct * the third argument to execve when executing a program. */ char ** environment(void) { int nenv; struct var **vpp; struct var *vp; char **env, **ep; nenv = 0; for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { for (vp = *vpp ; vp ; vp = vp->next) if (vp->flags & VEXPORT) nenv++; } ep = env = stalloc((nenv + 1) * sizeof *env); for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { for (vp = *vpp ; vp ; vp = vp->next) if (vp->flags & VEXPORT) *ep++ = vp->text; } *ep = NULL; return env; } /* * Called when a shell procedure is invoked to clear out nonexported * variables. It is also necessary to reallocate variables of with * VSTACK set since these are currently allocated on the stack. */ #ifdef mkinit MKINIT void shprocvar(void); SHELLPROC { shprocvar(); } #endif void shprocvar(void) { struct var **vpp; struct var *vp, **prev; for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { for (prev = vpp ; (vp = *prev) != NULL ; ) { if ((vp->flags & VEXPORT) == 0) { *prev = vp->next; if ((vp->flags & VTEXTFIXED) == 0) ckfree(vp->text); if ((vp->flags & VSTRFIXED) == 0) ckfree(vp); } else { if (vp->flags & VSTACK) { vp->text = savestr(vp->text); vp->flags &=~ VSTACK; } prev = &vp->next; } } } initvar(); } /* * Command to list all variables which are set. Currently this command * is invoked from the set command when the set command is called without * any variables. */ int showvarscmd(int argc __unused, char **argv __unused) { struct var **vpp; struct var *vp; const char *s; for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { for (vp = *vpp ; vp ; vp = vp->next) { if (vp->flags & VUNSET) continue; for (s = vp->text; *s != '='; s++) out1c(*s); out1c('='); out1qstr(s + 1); out1c('\n'); } } return 0; } /* * The export and readonly commands. */ int exportcmd(int argc, char **argv) { struct var **vpp; struct var *vp; char *name; char *p; char *cmdname; int ch, values; int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT; cmdname = argv[0]; optreset = optind = 1; opterr = 0; values = 0; while ((ch = getopt(argc, argv, "p")) != -1) { switch (ch) { case 'p': values = 1; break; case '?': default: error("unknown option: -%c", optopt); } } argc -= optind; argv += optind; listsetvar(cmdenviron); if (argc != 0) { while ((name = *argptr++) != NULL) { if ((p = strchr(name, '=')) != NULL) { p++; } else { vpp = hashvar(name); for (vp = *vpp ; vp ; vp = vp->next) { if (varequal(vp->text, name)) { vp->flags |= flag; if ((vp->flags & VEXPORT) && localevar(vp->text)) { putenv(vp->text); setlocale(LC_ALL, ""); } goto found; } } } setvar(name, p, flag); found:; } } else { for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) { for (vp = *vpp ; vp ; vp = vp->next) { if (vp->flags & flag) { if (values) { out1str(cmdname); out1c(' '); } for (p = vp->text ; *p != '=' ; p++) out1c(*p); if (values && !(vp->flags & VUNSET)) { out1c('='); out1qstr(p + 1); } out1c('\n'); } } } } return 0; } /* * The "local" command. */ int localcmd(int argc __unused, char **argv __unused) { char *name; if (! in_function()) error("Not in a function"); while ((name = *argptr++) != NULL) { mklocal(name); } return 0; } /* * Make a variable a local variable. When a variable is made local, it's * value and flags are saved in a localvar structure. The saved values * will be restored when the shell function returns. We handle the name * "-" as a special case. */ void mklocal(char *name) { struct localvar *lvp; struct var **vpp; struct var *vp; INTOFF; lvp = ckmalloc(sizeof (struct localvar)); if (name[0] == '-' && name[1] == '\0') { lvp->text = ckmalloc(sizeof optlist); memcpy(lvp->text, optlist, sizeof optlist); vp = NULL; } else { vpp = hashvar(name); for (vp = *vpp ; vp && ! varequal(vp->text, name) ; vp = vp->next); if (vp == NULL) { if (strchr(name, '=')) setvareq(savestr(name), VSTRFIXED); else setvar(name, NULL, VSTRFIXED); vp = *vpp; /* the new variable */ lvp->text = NULL; lvp->flags = VUNSET; } else { lvp->text = vp->text; lvp->flags = vp->flags; vp->flags |= VSTRFIXED|VTEXTFIXED; if (strchr(name, '=')) setvareq(savestr(name), 0); } } lvp->vp = vp; lvp->next = localvars; localvars = lvp; INTON; } /* * Called after a function returns. */ void poplocalvars(void) { struct localvar *lvp; struct var *vp; while ((lvp = localvars) != NULL) { localvars = lvp->next; vp = lvp->vp; if (vp == NULL) { /* $- saved */ memcpy(optlist, lvp->text, sizeof optlist); ckfree(lvp->text); } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) { unsetvar(vp->text); } else { if ((vp->flags & VTEXTFIXED) == 0) ckfree(vp->text); vp->flags = lvp->flags; vp->text = lvp->text; } ckfree(lvp); } } int setvarcmd(int argc, char **argv) { if (argc <= 2) return unsetcmd(argc, argv); else if (argc == 3) setvar(argv[1], argv[2], 0); else error("List assignment not implemented"); return 0; } /* * The unset builtin command. We unset the function before we unset the * variable to allow a function to be unset when there is a readonly variable * with the same name. */ int unsetcmd(int argc __unused, char **argv __unused) { char **ap; int i; int flg_func = 0; int flg_var = 0; int ret = 0; while ((i = nextopt("vf")) != '\0') { if (i == 'f') flg_func = 1; else flg_var = 1; } if (flg_func == 0 && flg_var == 0) flg_var = 1; for (ap = argptr; *ap ; ap++) { if (flg_func) ret |= unsetfunc(*ap); if (flg_var) ret |= unsetvar(*ap); } return ret; } /* * Unset the specified variable. */ int unsetvar(const char *s) { struct var **vpp; struct var *vp; vpp = hashvar(s); for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) { if (varequal(vp->text, s)) { if (vp->flags & VREADONLY) return (1); INTOFF; if (*(strchr(vp->text, '=') + 1) != '\0') setvar(s, nullstr, 0); if ((vp->flags & VEXPORT) && localevar(vp->text)) { unsetenv(s); setlocale(LC_ALL, ""); } vp->flags &= ~VEXPORT; vp->flags |= VUNSET; if ((vp->flags & VSTRFIXED) == 0) { if ((vp->flags & VTEXTFIXED) == 0) ckfree(vp->text); *vpp = vp->next; ckfree(vp); } INTON; return (0); } } return (0); } /* * Find the appropriate entry in the hash table from the name. */ STATIC struct var ** hashvar(const char *p) { unsigned int hashval; hashval = ((unsigned char) *p) << 4; while (*p && *p != '=') hashval += (unsigned char) *p++; return &vartab[hashval % VTABSIZE]; } /* * Returns true if the two strings specify the same varable. The first * variable name is terminated by '='; the second may be terminated by * either '=' or '\0'. */ STATIC int varequal(const char *p, const char *q) { while (*p == *q++) { if (*p++ == '=') return 1; } if (*p == '=' && *(q - 1) == '\0') return 1; return 0; }