/* $OpenBSD: var.c,v 1.98 2014/05/12 19:11:19 espie Exp $ */ /* $NetBSD: var.c,v 1.18 1997/03/18 19:24:46 christos Exp $ */ /* * Copyright (c) 1999,2000,2007 Marc Espie. * * Extensive code modifications for the OpenBSD project. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT 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 OPENBSD * PROJECT 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. */ /* * Copyright (c) 1988, 1989, 1990, 1993 * The Regents of the University of California. All rights reserved. * Copyright (c) 1989 by Berkeley Softworks * All rights reserved. * * This code is derived from software contributed to Berkeley by * Adam de Boor. * * 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. 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. */ #include <assert.h> #include <stddef.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <ohash.h> #include "config.h" #include "defines.h" #include "buf.h" #include "stats.h" #include "pathnames.h" #include "varmodifiers.h" #include "var.h" #include "varname.h" #include "error.h" #include "str.h" #include "var_int.h" #include "memory.h" #include "symtable.h" #include "gnode.h" #include "dump.h" #include "lowparse.h" /* * This is a harmless return value for Var_Parse that can be used by Var_Subst * to determine if there was an error in parsing -- easier than returning * a flag, as things outside this module don't give a hoot. */ char var_Error[] = ""; GNode *current_node = NULL; /* * Similar to var_Error, but returned when the 'err' flag for Var_Parse is * set false. Why not just use a constant? Well, gcc likes to condense * identical string instances... */ static char varNoError[] = ""; bool errorIsOkay; static bool checkEnvFirst; /* true if environment should be searched for * variables before the global context */ void Var_setCheckEnvFirst(bool yes) { checkEnvFirst = yes; } /* * The rules for variable look-up are complicated. * * - Dynamic variables like $@ and $* are special. They always pertain to * a given variable. In this implementation of make, it is an error to * try to affect them manually. They are stored in a local symtable directly * inside the gnode. * * Global variables can be obtained: * - from the command line * - from the environment * - from the Makefile proper. * All of these are stored in a hash global_variables. * * Variables set on the command line override Makefile contents, are * passed to submakes (see Var_AddCmdLine), and are also exported to the * environment. * * Without -e (!checkEnvFirst), make will see variables set in the * Makefile, and default to the environment otherwise. * * With -e (checkEnvFirst), make will see the environment first, and that * will override anything that's set in the Makefile (but not set on * the command line). * * The SHELL variable is very special: it is never obtained from the * environment, and never passed to the environment. */ /* definitions pertaining to dynamic variables */ /* full names of dynamic variables */ static char *varnames[] = { TARGET, PREFIX, ARCHIVE, MEMBER, OODATE, ALLSRC, IMPSRC, FTARGET, DTARGET, FPREFIX, DPREFIX, FARCHIVE, DARCHIVE, FMEMBER, DMEMBER }; static bool xtlist[] = { false, /* GLOBAL_INDEX */ true, /* $@ */ false, /* $* */ false, /* $! */ true, /* $% */ false, /* $? */ false, /* $> */ true, /* $< */ true, /* ${@F} */ true, /* ${@D} */ false, /* ${*F} */ false, /* ${*D} */ false, /* ${!F} */ false, /* ${!D} */ true, /* ${%F} */ true, /* ${%D} */ }; /* so that we can access tlist[-1] */ static bool *tlist = xtlist+1; /* hashed names of dynamic variables */ #include "varhashconsts.h" /* extended indices for System V stuff */ #define FTARGET_INDEX 7 #define DTARGET_INDEX 8 #define FPREFIX_INDEX 9 #define DPREFIX_INDEX 10 #define FARCHIVE_INDEX 11 #define DARCHIVE_INDEX 12 #define FMEMBER_INDEX 13 #define DMEMBER_INDEX 14 #define GLOBAL_INDEX -1 #define EXTENDED2SIMPLE(i) (((i)-LOCAL_SIZE)/2) #define IS_EXTENDED_F(i) ((i)%2 == 1) static struct ohash global_variables; typedef struct Var_ { BUFFER val; /* the variable value */ unsigned int flags; /* miscellaneous status flags */ #define VAR_IN_USE 1 /* Variable's value currently being used. */ /* (Used to avoid recursion) */ #define VAR_DUMMY 2 /* Variable is currently just a name */ /* In particular: BUFFER is invalid */ #define VAR_FROM_CMD 4 /* Special source: command line */ #define VAR_FROM_ENV 8 /* Special source: environment */ #define VAR_SEEN_ENV 16 /* No need to go look up environment again */ #define VAR_SHELL 32 /* Magic behavior */ #define POISONS (POISON_NORMAL | POISON_EMPTY | POISON_NOT_DEFINED) /* Defined in var.h */ char name[1]; /* the variable's name */ } Var; static struct ohash_info var_info = { offsetof(Var, name), NULL, hash_calloc, hash_free, element_alloc }; static int classify_var(const char *, const char **, uint32_t *); static Var *find_global_var(const char *, const char *, uint32_t); static Var *find_global_var_without_env(const char *, const char *, uint32_t); static void fill_from_env(Var *); static Var *create_var(const char *, const char *); static void var_set_initial_value(Var *, const char *); static void var_set_value(Var *, const char *); #define var_get_value(v) Buf_Retrieve(&((v)->val)) static void var_append_value(Var *, const char *); static void poison_check(Var *); static void var_set_append(const char *, const char *, const char *, int, bool); static void set_magic_shell_variable(void); static void delete_var(Var *); static void print_var(Var *); static const char *find_rparen(const char *); static const char *find_ket(const char *); typedef const char * (*find_t)(const char *); static find_t find_pos(int); static void push_used(Var *); static void pop_used(Var *); static char *get_expanded_value(const char *, const char *, int, uint32_t, SymTable *, bool, bool *); static bool parse_base_variable_name(const char **, struct Name *, SymTable *); /* Variable lookup function: return idx for dynamic variable, or * GLOBAL_INDEX if name is not dynamic. Set up *pk for further use. */ static int classify_var(const char *name, const char **enamePtr, uint32_t *pk) { size_t len; *pk = ohash_interval(name, enamePtr); len = *enamePtr - name; /* substitute short version for long local name */ switch (*pk % MAGICSLOTS1) { /* MAGICSLOTS should be the */ case K_LONGALLSRC % MAGICSLOTS1:/* smallest constant yielding */ /* distinct case values */ if (*pk == K_LONGALLSRC && len == strlen(LONGALLSRC) && strncmp(name, LONGALLSRC, len) == 0) return ALLSRC_INDEX; break; case K_LONGARCHIVE % MAGICSLOTS1: if (*pk == K_LONGARCHIVE && len == strlen(LONGARCHIVE) && strncmp(name, LONGARCHIVE, len) == 0) return ARCHIVE_INDEX; break; case K_LONGIMPSRC % MAGICSLOTS1: if (*pk == K_LONGIMPSRC && len == strlen(LONGIMPSRC) && strncmp(name, LONGIMPSRC, len) == 0) return IMPSRC_INDEX; break; case K_LONGMEMBER % MAGICSLOTS1: if (*pk == K_LONGMEMBER && len == strlen(LONGMEMBER) && strncmp(name, LONGMEMBER, len) == 0) return MEMBER_INDEX; break; case K_LONGOODATE % MAGICSLOTS1: if (*pk == K_LONGOODATE && len == strlen(LONGOODATE) && strncmp(name, LONGOODATE, len) == 0) return OODATE_INDEX; break; case K_LONGPREFIX % MAGICSLOTS1: if (*pk == K_LONGPREFIX && len == strlen(LONGPREFIX) && strncmp(name, LONGPREFIX, len) == 0) return PREFIX_INDEX; break; case K_LONGTARGET % MAGICSLOTS1: if (*pk == K_LONGTARGET && len == strlen(LONGTARGET) && strncmp(name, LONGTARGET, len) == 0) return TARGET_INDEX; break; case K_TARGET % MAGICSLOTS1: if (name[0] == TARGET[0] && len == 1) return TARGET_INDEX; break; case K_OODATE % MAGICSLOTS1: if (name[0] == OODATE[0] && len == 1) return OODATE_INDEX; break; case K_ALLSRC % MAGICSLOTS1: if (name[0] == ALLSRC[0] && len == 1) return ALLSRC_INDEX; break; case K_IMPSRC % MAGICSLOTS1: if (name[0] == IMPSRC[0] && len == 1) return IMPSRC_INDEX; break; case K_PREFIX % MAGICSLOTS1: if (name[0] == PREFIX[0] && len == 1) return PREFIX_INDEX; break; case K_ARCHIVE % MAGICSLOTS1: if (name[0] == ARCHIVE[0] && len == 1) return ARCHIVE_INDEX; break; case K_MEMBER % MAGICSLOTS1: if (name[0] == MEMBER[0] && len == 1) return MEMBER_INDEX; break; case K_FTARGET % MAGICSLOTS1: if (name[0] == FTARGET[0] && name[1] == FTARGET[1] && len == 2) return FTARGET_INDEX; break; case K_DTARGET % MAGICSLOTS1: if (name[0] == DTARGET[0] && name[1] == DTARGET[1] && len == 2) return DTARGET_INDEX; break; case K_FPREFIX % MAGICSLOTS1: if (name[0] == FPREFIX[0] && name[1] == FPREFIX[1] && len == 2) return FPREFIX_INDEX; break; case K_DPREFIX % MAGICSLOTS1: if (name[0] == DPREFIX[0] && name[1] == DPREFIX[1] && len == 2) return DPREFIX_INDEX; break; case K_FARCHIVE % MAGICSLOTS1: if (name[0] == FARCHIVE[0] && name[1] == FARCHIVE[1] && len == 2) return FARCHIVE_INDEX; break; case K_DARCHIVE % MAGICSLOTS1: if (name[0] == DARCHIVE[0] && name[1] == DARCHIVE[1] && len == 2) return DARCHIVE_INDEX; break; case K_FMEMBER % MAGICSLOTS1: if (name[0] == FMEMBER[0] && name[1] == FMEMBER[1] && len == 2) return FMEMBER_INDEX; break; case K_DMEMBER % MAGICSLOTS1: if (name[0] == DMEMBER[0] && name[1] == DMEMBER[1] && len == 2) return DMEMBER_INDEX; break; default: break; } return GLOBAL_INDEX; } /*** *** Internal handling of variables. ***/ /* Create a new variable, does not initialize anything except the name. * in particular, buffer is invalid, and flag value is invalid. Accordingly, * must either: * - set flags to VAR_DUMMY * - set flags to !VAR_DUMMY, and initialize buffer, for instance with * var_set_initial_value(). */ static Var * create_var(const char *name, const char *ename) { return ohash_create_entry(&var_info, name, &ename); } /* Initial version of var_set_value(), to be called after create_var(). */ static void var_set_initial_value(Var *v, const char *val) { size_t len; len = strlen(val); Buf_Init(&(v->val), len+1); Buf_AddChars(&(v->val), len, val); } /* Normal version of var_set_value(), to be called after variable is fully * initialized. */ static void var_set_value(Var *v, const char *val) { if ((v->flags & VAR_DUMMY) == 0) { Buf_Reset(&(v->val)); Buf_AddString(&(v->val), val); } else { var_set_initial_value(v, val); v->flags &= ~VAR_DUMMY; } } /* Add to a variable, insert a separating space if the variable was already * defined. */ static void var_append_value(Var *v, const char *val) { if ((v->flags & VAR_DUMMY) == 0) { Buf_AddSpace(&(v->val)); Buf_AddString(&(v->val), val); } else { var_set_initial_value(v, val); v->flags &= ~VAR_DUMMY; } } /* Delete a variable and all the space associated with it. */ static void delete_var(Var *v) { if ((v->flags & VAR_DUMMY) == 0) Buf_Destroy(&(v->val)); free(v); } /*** *** Dynamic variable handling. ***/ /* create empty symtable. * XXX: to save space, dynamic variables may be NULL pointers. */ void SymTable_Init(SymTable *ctxt) { static SymTable sym_template; memcpy(ctxt, &sym_template, sizeof(*ctxt)); } /*** *** Global variable handling. ***/ /* Create a new global var if necessary, and set it up correctly. * Do not take environment into account. */ static Var * find_global_var_without_env(const char *name, const char *ename, uint32_t k) { unsigned int slot; Var *v; slot = ohash_lookup_interval(&global_variables, name, ename, k); v = ohash_find(&global_variables, slot); if (v == NULL) { v = create_var(name, ename); v->flags = VAR_DUMMY; ohash_insert(&global_variables, slot, v); } return v; } /* Helper for find_global_var(): grab environment value if needed. */ static void fill_from_env(Var *v) { char *env; env = getenv(v->name); if (env == NULL) v->flags |= VAR_SEEN_ENV; else { var_set_value(v, env); v->flags |= VAR_FROM_ENV | VAR_SEEN_ENV; } #ifdef STATS_VAR_LOOKUP STAT_VAR_FROM_ENV++; #endif } /* Find global var, and obtain its value from the environment if needed. */ static Var * find_global_var(const char *name, const char *ename, uint32_t k) { Var *v; v = find_global_var_without_env(name, ename, k); if ((v->flags & VAR_SEEN_ENV) == 0) if ((checkEnvFirst && (v->flags & VAR_FROM_CMD) == 0) || (v->flags & VAR_DUMMY) != 0) fill_from_env(v); return v; } /* mark variable as poisoned, in a given setup. */ void Var_MarkPoisoned(const char *name, const char *ename, unsigned int type) { Var *v; uint32_t k; int idx; idx = classify_var(name, &ename, &k); if (idx != GLOBAL_INDEX) { Parse_Error(PARSE_FATAL, "Trying to poison dynamic variable $%s", varnames[idx]); return; } v = find_global_var(name, ename, k); v->flags |= type; /* POISON_NORMAL is not lazy: if the variable already exists in * the Makefile, then it's a mistake. */ if (v->flags & POISON_NORMAL) { if (v->flags & VAR_DUMMY) return; if (v->flags & VAR_FROM_ENV) return; Parse_Error(PARSE_FATAL, "Poisoned variable %s is already set\n", v->name); } } /* Check if there's any reason not to use the variable in this context. */ static void poison_check(Var *v) { if (v->flags & POISON_NORMAL) { Parse_Error(PARSE_FATAL, "Poisoned variable %s has been referenced\n", v->name); return; } if (v->flags & VAR_DUMMY) { Parse_Error(PARSE_FATAL, "Poisoned variable %s is not defined\n", v->name); return; } if (v->flags & POISON_EMPTY) if (strcmp(var_get_value(v), "") == 0) Parse_Error(PARSE_FATAL, "Poisoned variable %s is empty\n", v->name); } /* Delete global variable. */ void Var_Deletei(const char *name, const char *ename) { Var *v; uint32_t k; unsigned int slot; int idx; idx = classify_var(name, &ename, &k); if (idx != GLOBAL_INDEX) { Parse_Error(PARSE_FATAL, "Trying to delete dynamic variable $%s", varnames[idx]); return; } slot = ohash_lookup_interval(&global_variables, name, ename, k); v = ohash_find(&global_variables, slot); if (v == NULL) return; if (checkEnvFirst && (v->flags & VAR_FROM_ENV)) return; if (v->flags & VAR_FROM_CMD) return; ohash_remove(&global_variables, slot); delete_var(v); } /* Set or add a global variable, in VAR_CMD or VAR_GLOBAL context. */ static void var_set_append(const char *name, const char *ename, const char *val, int ctxt, bool append) { Var *v; uint32_t k; int idx; idx = classify_var(name, &ename, &k); if (idx != GLOBAL_INDEX) { Parse_Error(PARSE_FATAL, "Trying to %s dynamic variable $%s", append ? "append to" : "set", varnames[idx]); return; } v = find_global_var(name, ename, k); if (v->flags & POISON_NORMAL) Parse_Error(PARSE_FATAL, "Trying to %s poisoned variable %s\n", append ? "append to" : "set", v->name); /* so can we write to it ? */ if (ctxt == VAR_CMD) { /* always for command line */ (append ? var_append_value : var_set_value)(v, val); v->flags |= VAR_FROM_CMD; if ((v->flags & VAR_SHELL) == 0) { /* Any variables given on the command line are * automatically exported to the environment, * except for SHELL (as per POSIX standard). */ esetenv(v->name, val); } if (DEBUG(VAR)) printf("command:%s = %s\n", v->name, var_get_value(v)); } else if ((v->flags & VAR_FROM_CMD) == 0 && (!checkEnvFirst || (v->flags & VAR_FROM_ENV) == 0)) { (append ? var_append_value : var_set_value)(v, val); if (DEBUG(VAR)) printf("global:%s = %s\n", v->name, var_get_value(v)); } else if (DEBUG(VAR)) printf("overridden:%s = %s\n", v->name, var_get_value(v)); } void Var_Seti_with_ctxt(const char *name, const char *ename, const char *val, int ctxt) { var_set_append(name, ename, val, ctxt, false); } void Var_Appendi_with_ctxt(const char *name, const char *ename, const char *val, int ctxt) { var_set_append(name, ename, val, ctxt, true); } /* XXX different semantics for Var_Valuei() and Var_Definedi(): * references to poisoned value variables will error out in Var_Valuei(), * but not in Var_Definedi(), so the following construct works: * .poison BINDIR * BINDIR ?= /usr/bin */ char * Var_Valuei(const char *name, const char *ename) { Var *v; uint32_t k; int idx; idx = classify_var(name, &ename, &k); if (idx != GLOBAL_INDEX) { Parse_Error(PARSE_FATAL, "Trying to get value of dynamic variable $%s", varnames[idx]); return NULL; } v = find_global_var(name, ename, k); if (v->flags & POISONS) poison_check(v); if ((v->flags & VAR_DUMMY) == 0) return var_get_value(v); else return NULL; } bool Var_Definedi(const char *name, const char *ename) { Var *v; uint32_t k; int idx; idx = classify_var(name, &ename, &k); /* We don't bother writing an error message for dynamic variables, * these will be caught when getting set later, usually. */ if (idx == GLOBAL_INDEX) { v = find_global_var(name, ename, k); if (v->flags & POISON_NORMAL) poison_check(v); if ((v->flags & VAR_DUMMY) == 0) return true; } return false; } /*** *** Substitution functions, handling both global and dynamic variables. ***/ /* All the scanning functions needed to account for all the forms of * variable names that exist: * $A, ${AB}, $(ABC), ${A:mod}, $(A:mod) */ static const char * find_rparen(const char *p) { while (*p != '$' && *p != '\0' && *p != ')' && *p != ':') p++; return p; } static const char * find_ket(const char *p) { while (*p != '$' && *p != '\0' && *p != '}' && *p != ':') p++; return p; } /* Figure out what kind of name we're looking for from a start character. */ static find_t find_pos(int c) { switch(c) { case '(': return find_rparen; case '{': return find_ket; default: Parse_Error(PARSE_FATAL, "Wrong character in variable spec %c (can't happen)"); return find_rparen; } } static bool parse_base_variable_name(const char **pstr, struct Name *name, SymTable *ctxt) { const char *str = *pstr; const char *tstr; bool has_modifier = false; switch(str[1]) { case '(': case '{': /* Find eventual modifiers in the variable */ tstr = VarName_Get(str+2, name, ctxt, false, find_pos(str[1])); if (*tstr == '\0') Parse_Error(PARSE_FATAL, "Unterminated variable spec in %s", *pstr); else if (*tstr == ':') has_modifier = true; else tstr++; break; default: name->s = str+1; name->e = str+2; name->tofree = false; tstr = str + 2; break; } *pstr = tstr; return has_modifier; } bool Var_ParseSkip(const char **pstr, SymTable *ctxt) { const char *str = *pstr; struct Name name; bool result; bool has_modifier; const char *tstr = str; if (str[1] == 0) { *pstr = str+1; return false; } has_modifier = parse_base_variable_name(&tstr, &name, ctxt); VarName_Free(&name); result = true; if (has_modifier) { bool freePtr = false; char *s = VarModifiers_Apply(NULL, NULL, ctxt, true, &freePtr, &tstr, str[1]); if (s == var_Error) result = false; if (freePtr) free(s); } *pstr = tstr; return result; } /* As of now, Var_ParseBuffer is just a wrapper around Var_Parse. For * speed, it may be better to revisit the implementation to do things * directly. */ bool Var_ParseBuffer(Buffer buf, const char *str, SymTable *ctxt, bool err, size_t *lengthPtr) { char *result; bool freeIt; result = Var_Parse(str, ctxt, err, lengthPtr, &freeIt); if (result == var_Error) return false; Buf_AddString(buf, result); if (freeIt) free(result); return true; } /* Helper function for Var_Parse: still recursive, but we tag what variables * we expand for better error messages. */ #define MAX_DEPTH 350 static Var *call_trace[MAX_DEPTH]; static int current_depth = 0; static void push_used(Var *v) { if (v->flags & VAR_IN_USE) { int i; fprintf(stderr, "Problem with variable expansion chain: "); for (i = 0; i < (current_depth > MAX_DEPTH ? MAX_DEPTH : current_depth); i++) fprintf(stderr, "%s -> ", call_trace[i]->name); fprintf(stderr, "%s\n", v->name); Fatal("\tVariable %s is recursive.", v->name); /*NOTREACHED*/ } v->flags |= VAR_IN_USE; if (current_depth < MAX_DEPTH) call_trace[current_depth] = v; current_depth++; } static void pop_used(Var *v) { v->flags &= ~VAR_IN_USE; current_depth--; } static char * get_expanded_value(const char *name, const char *ename, int idx, uint32_t k, SymTable *ctxt, bool err, bool *freePtr) { char *val; /* Before doing any modification, we have to make sure the * value has been fully expanded. If it looks like recursion * might be necessary (there's a dollar sign somewhere in * the variable's value) we just call Var_Subst to do any * other substitutions that are necessary. Note that the * value returned by Var_Subst will have been dynamically * allocated, so it will need freeing when we return. */ if (idx == GLOBAL_INDEX) { Var *v = find_global_var(name, ename, k); if (v == NULL) return NULL; if ((v->flags & POISONS) != 0) poison_check(v); if ((v->flags & VAR_DUMMY) != 0) return NULL; val = var_get_value(v); if (strchr(val, '$') != NULL) { push_used(v); val = Var_Subst(val, ctxt, err); pop_used(v); *freePtr = true; } } else { if (ctxt != NULL) { if (idx < LOCAL_SIZE) val = ctxt->locals[idx]; else val = ctxt->locals[EXTENDED2SIMPLE(idx)]; } else val = NULL; if (val == NULL) return NULL; if (idx >= LOCAL_SIZE) { if (IS_EXTENDED_F(idx)) val = Var_GetTail(val); else val = Var_GetHead(val); *freePtr = true; } } return val; } #define ERRMSG1 "Using $< in a non-suffix rule context is a GNUmake idiom " #define ERRMSG2 "Using undefined dynamic variable $%s " static void bad_dynamic_variable(int idx) { Location origin; Parse_FillLocation(&origin); if (idx >= LOCAL_SIZE) idx = EXTENDED2SIMPLE(idx); switch(idx) { case IMPSRC_INDEX: if (origin.fname) Fatal(ERRMSG1 "(%s:%lu)", origin.fname, origin.lineno); else if (current_node) Fatal(ERRMSG1 "(prereq of %s)", current_node->name); else Fatal(ERRMSG1 "(?)"); break; default: if (origin.fname) Error(ERRMSG2 "(%s:%lu)", varnames[idx], origin.fname, origin.lineno); else if (current_node) Error(ERRMSG2 "(prereq of %s)", varnames[idx], current_node->name); else Error(ERRMSG2 "(?)", varnames[idx]); break; } } char * Var_Parse(const char *str, /* The string to parse */ SymTable *ctxt, /* The context for the variable */ bool err, /* true if undefined variables are an error */ size_t *lengthPtr, /* OUT: The length of the specification */ bool *freePtr) /* OUT: true if caller should free result */ { const char *tstr; struct Name name; char *val; uint32_t k; int idx; bool has_modifier; *freePtr = false; tstr = str; if (str[1] == 0) { *lengthPtr = 1; *freePtr = false; return err ? var_Error : varNoError; } has_modifier = parse_base_variable_name(&tstr, &name, ctxt); idx = classify_var(name.s, &name.e, &k); val = get_expanded_value(name.s, name.e, idx, k, ctxt, err, freePtr); if (has_modifier) { val = VarModifiers_Apply(val, &name, ctxt, err, freePtr, &tstr, str[1]); } if (val == NULL) { val = err ? var_Error : varNoError; /* If it comes from a dynamic source, and it doesn't have * a context, copy the spec instead. * Specifically, this make allows constructs like: * target.o: $*.c * Absence of a context means "parsing". But these can't * be expanded during parsing, to be consistent with the * way .SUFFIXES work. * .SUFFIXES may be added/reset/removed during parsing, * but in the end, the final list is what's considered for * handling targets. So those dynamic variables must be * handled lazily too. */ if (idx != GLOBAL_INDEX) { if (ctxt == NULL) { *freePtr = true; val = Str_dupi(str, tstr); } else { bad_dynamic_variable(idx); } } } VarName_Free(&name); *lengthPtr = tstr - str; return val; } char * Var_Subst(const char *str, /* the string in which to substitute */ SymTable *ctxt, /* the context wherein to find variables */ bool undefErr) /* true if undefineds are an error */ { BUFFER buf; /* Buffer for forming things */ static bool errorReported; Buf_Init(&buf, MAKE_BSIZE); errorReported = false; for (;;) { char *val; /* Value to substitute for a variable */ size_t length; /* Length of the variable invocation */ bool doFree; /* Set true if val should be freed */ const char *cp; /* copy uninteresting stuff */ for (cp = str; *str != '\0' && *str != '$'; str++) ; Buf_Addi(&buf, cp, str); if (*str == '\0') break; if (str[1] == '$') { /* A $ may be escaped with another $. */ Buf_AddChar(&buf, '$'); str += 2; continue; } val = Var_Parse(str, ctxt, undefErr, &length, &doFree); /* When we come down here, val should either point to the * value of this variable, suitably modified, or be NULL. * Length should be the total length of the potential * variable invocation (from $ to end character...) */ if (val == var_Error || val == varNoError) { /* If errors are not an issue, skip over the variable * and continue with the substitution. Otherwise, store * the dollar sign and advance str so we continue with * the string... */ if (errorIsOkay) str += length; else if (undefErr) { /* If variable is undefined, complain and * skip the variable name. The complaint * will stop us from doing anything when * the file is parsed. */ if (!errorReported) Parse_Error(PARSE_FATAL, "Undefined variable \"%.*s\"", length, str); str += length; errorReported = true; } else { Buf_AddChar(&buf, *str); str++; } } else { /* We've now got a variable structure to store in. * But first, advance the string pointer. */ str += length; /* Copy all the characters from the variable value * straight into the new string. */ Buf_AddString(&buf, val); if (doFree) free(val); } } return Buf_Retrieve(&buf); } /* Very quick version of the variable scanner that just looks for target * variables, and never ever errors out */ bool Var_Check_for_target(const char *str) { bool seen_target = false; for (;;) { const char *tstr; uint32_t k; int idx; bool has_modifier; struct Name name; /* skip over uninteresting stuff */ for (; *str != '\0' && *str != '$'; str++) ; if (*str == '\0') break; if (str[1] == '$') { /* A $ may be escaped with another $. */ str += 2; continue; } tstr = str; has_modifier = parse_base_variable_name(&tstr, &name, NULL); idx = classify_var(name.s, &name.e, &k); if (has_modifier) { bool doFree = false; char *val = VarModifiers_Apply(NULL, NULL, NULL, false, &doFree, &tstr, str[1]); if (doFree) free(val); } if (tlist[idx]) seen_target = true; VarName_Free(&name); str = tstr; } return seen_target; } static BUFFER subst_buffer; /* we would like to subst on intervals, but it's complicated, so we cheat * by storing the interval in a static buffer. */ char * Var_Substi(const char *str, const char *estr, SymTable *ctxt, bool undefErr) { /* delimited string: no need to copy */ if (estr == NULL || *estr == '\0') return Var_Subst(str, ctxt, undefErr); Buf_Reset(&subst_buffer); Buf_Addi(&subst_buffer, str, estr); return Var_Subst(Buf_Retrieve(&subst_buffer), ctxt, undefErr); } /*** *** Supplementary support for .for loops. ***/ struct LoopVar { Var old; /* keep old variable value (before the loop) */ Var *me; /* the variable we're dealing with */ }; struct LoopVar * Var_NewLoopVar(const char *name, const char *ename) { struct LoopVar *l; uint32_t k; l = emalloc(sizeof(struct LoopVar)); /* we obtain a new variable quickly, make a snapshot of its old * value, and make sure the environment cannot touch us. */ /* XXX: should we avoid dynamic variables ? */ k = ohash_interval(name, &ename); l->me = find_global_var_without_env(name, ename, k); l->old = *(l->me); l->me->flags = VAR_SEEN_ENV | VAR_DUMMY; return l; } char * Var_LoopVarName(struct LoopVar *v) { return v->me->name; } void Var_DeleteLoopVar(struct LoopVar *l) { if ((l->me->flags & VAR_DUMMY) == 0) Buf_Destroy(&(l->me->val)); *(l->me) = l->old; free(l); } void Var_SubstVar(Buffer buf, /* To store result */ const char *str, /* The string in which to substitute */ struct LoopVar *l, /* Handle */ const char *val) /* Its value */ { const char *var = l->me->name; var_set_value(l->me, val); for (;;) { const char *start; /* Copy uninteresting stuff */ for (start = str; *str != '\0' && *str != '$'; str++) ; Buf_Addi(buf, start, str); start = str; if (*str++ == '\0') break; str++; /* and escaped dollars */ if (start[1] == '$') { Buf_Addi(buf, start, start+2); continue; } /* Simple variable, if it's not us, copy. */ if (start[1] != '(' && start[1] != '{') { if (start[1] != *var || var[1] != '\0') { Buf_AddChars(buf, 2, start); continue; } } else { const char *p; char paren = start[1]; /* Find the end of the variable specification. */ p = find_pos(paren)(str); /* A variable inside the variable. We don't know how to * expand the external variable at this point, so we * try again with the nested variable. */ if (*p == '$') { Buf_Addi(buf, start, p); str = p; continue; } if (strncmp(var, str, p - str) != 0 || var[p - str] != '\0') { /* Not the variable we want to expand. */ Buf_Addi(buf, start, p); str = p; continue; } if (*p == ':') { bool doFree; /* should val be freed ? */ char *newval; struct Name name; doFree = false; name.s = var; name.e = var + (p-str); /* val won't be freed since !doFree, but * VarModifiers_Apply doesn't know that, * hence the cast. */ newval = VarModifiers_Apply((char *)val, &name, NULL, false, &doFree, &p, paren); Buf_AddString(buf, newval); if (doFree) free(newval); str = p; continue; } else str = p+1; } Buf_AddString(buf, val); } } /*** *** Odds and ends ***/ static void set_magic_shell_variable() { const char *name = "SHELL"; const char *ename = NULL; uint32_t k; Var *v; k = ohash_interval(name, &ename); v = find_global_var_without_env(name, ename, k); var_set_value(v, _PATH_BSHELL); /* XXX the environment shall never affect it */ v->flags = VAR_SHELL | VAR_SEEN_ENV; } /* * Var_Init * Initialize the module */ void Var_Init(void) { ohash_init(&global_variables, 10, &var_info); set_magic_shell_variable(); errorIsOkay = true; Var_setCheckEnvFirst(false); VarModifiers_Init(); Buf_Init(&subst_buffer, MAKE_BSIZE); } static const char *interpret(int); static const char * interpret(int f) { if (f & VAR_DUMMY) return "(D)"; return ""; } static void print_var(Var *v) { printf("%-16s%s = %s\n", v->name, interpret(v->flags), (v->flags & VAR_DUMMY) == 0 ? var_get_value(v) : "(none)"); } void Var_Dump(void) { Var **t; unsigned int i; const char *banner; bool first = true; t = sort_ohash_by_name(&global_variables); /* somewhat dirty, but does the trick */ #define LOOP(mask, value, do_stuff) \ for (i = 0; t[i] != NULL; i++) \ if ((t[i]->flags & (mask)) == (value)) { \ if (banner) { \ if (first) \ first = false; \ else \ putchar('\n'); \ fputs(banner, stdout); \ banner = NULL; \ } \ do_stuff; \ } banner = "#variables from command line:\n"; LOOP(VAR_FROM_CMD | VAR_DUMMY, VAR_FROM_CMD, print_var(t[i])); banner = "#global variables:\n"; LOOP(VAR_FROM_ENV| VAR_FROM_CMD | VAR_DUMMY, 0, print_var(t[i])); banner = "#variables from env:\n"; LOOP(VAR_FROM_ENV|VAR_DUMMY, VAR_FROM_ENV, print_var(t[i])); banner = "#variable name seen, but not defined:"; LOOP(VAR_DUMMY|POISONS, VAR_DUMMY, printf(" %s", t[i]->name)); #undef LOOP printf("\n\n"); for (i = 0; t[i] != NULL; i++) switch(t[i]->flags & POISONS) { case POISON_NORMAL: printf(".poison %s\n", t[i]->name); break; case POISON_EMPTY: printf(".poison empty(%s)\n", t[i]->name); break; case POISON_NOT_DEFINED: printf(".poison !defined(%s)\n", t[i]->name); break; default: break; } free(t); printf("\n"); } static const char *quotable = " \t\n\\'\""; /* POSIX says that variable assignments passed on the command line should be * propagated to sub makes through MAKEFLAGS. */ void Var_AddCmdline(const char *name) { Var *v; unsigned int i; BUFFER buf; char *s; Buf_Init(&buf, MAKE_BSIZE); for (v = ohash_first(&global_variables, &i); v != NULL; v = ohash_next(&global_variables, &i)) { /* This is not as expensive as it looks: this function is * called before parsing Makefiles, so there are just a * few non cmdling variables in there. */ if (!(v->flags & VAR_FROM_CMD)) { continue; } /* We assume variable names don't need quoting */ Buf_AddString(&buf, v->name); Buf_AddChar(&buf, '='); for (s = var_get_value(v); *s != '\0'; s++) { if (strchr(quotable, *s)) Buf_AddChar(&buf, '\\'); Buf_AddChar(&buf, *s); } Buf_AddSpace(&buf); } Var_Append(name, Buf_Retrieve(&buf)); Buf_Destroy(&buf); }