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Diffstat (limited to 'rule.c')
| -rw-r--r-- | rule.c | 533 |
1 files changed, 533 insertions, 0 deletions
@@ -0,0 +1,533 @@ +/* Pattern and suffix rule internals for GNU Make. +Copyright (C) 1988-2014 Free Software Foundation, Inc. +This file is part of GNU Make. + +GNU Make is free software; you can redistribute it and/or modify it under the +terms of the GNU General Public License as published by the Free Software +Foundation; either version 3 of the License, or (at your option) any later +version. + +GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +A PARTICULAR PURPOSE. See the GNU General Public License for more details. + +You should have received a copy of the GNU General Public License along with +this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "makeint.h" + +#include <assert.h> + +#include "filedef.h" +#include "dep.h" +#include "job.h" +#include "commands.h" +#include "variable.h" +#include "rule.h" + +static void freerule (struct rule *rule, struct rule *lastrule); + +/* Chain of all pattern rules. */ + +struct rule *pattern_rules; + +/* Pointer to last rule in the chain, so we can add onto the end. */ + +struct rule *last_pattern_rule; + +/* Number of rules in the chain. */ + +unsigned int num_pattern_rules; + +/* Maximum number of target patterns of any pattern rule. */ + +unsigned int max_pattern_targets; + +/* Maximum number of dependencies of any pattern rule. */ + +unsigned int max_pattern_deps; + +/* Maximum length of the name of a dependencies of any pattern rule. */ + +unsigned int max_pattern_dep_length; + +/* Pointer to structure for the file .SUFFIXES + whose dependencies are the suffixes to be searched. */ + +struct file *suffix_file; + +/* Maximum length of a suffix. */ + +unsigned int maxsuffix; + +/* Compute the maximum dependency length and maximum number of + dependencies of all implicit rules. Also sets the subdir + flag for a rule when appropriate, possibly removing the rule + completely when appropriate. */ + +void +count_implicit_rule_limits (void) +{ + char *name; + int namelen; + struct rule *rule; + + num_pattern_rules = max_pattern_targets = max_pattern_deps = 0; + max_pattern_dep_length = 0; + + name = 0; + namelen = 0; + rule = pattern_rules; + while (rule != 0) + { + unsigned int ndeps = 0; + struct dep *dep; + struct rule *next = rule->next; + + ++num_pattern_rules; + + if (rule->num > max_pattern_targets) + max_pattern_targets = rule->num; + + for (dep = rule->deps; dep != 0; dep = dep->next) + { + const char *dname = dep_name (dep); + unsigned int len = strlen (dname); + +#ifdef VMS + const char *p = strrchr (dname, ']'); + const char *p2; + if (p == 0) + p = strrchr (dname, ':'); + p2 = p != 0 ? strchr (dname, '%') : 0; +#else + const char *p = strrchr (dname, '/'); + const char *p2 = p != 0 ? strchr (dname, '%') : 0; +#endif + ndeps++; + + if (len > max_pattern_dep_length) + max_pattern_dep_length = len; + + if (p != 0 && p2 > p) + { + /* There is a slash before the % in the dep name. + Extract the directory name. */ + if (p == dname) + ++p; + if (p - dname > namelen) + { + namelen = p - dname; + name = xrealloc (name, namelen + 1); + } + memcpy (name, dname, p - dname); + name[p - dname] = '\0'; + + /* In the deps of an implicit rule the 'changed' flag + actually indicates that the dependency is in a + nonexistent subdirectory. */ + + dep->changed = !dir_file_exists_p (name, ""); + } + else + /* This dependency does not reside in a subdirectory. */ + dep->changed = 0; + } + + if (ndeps > max_pattern_deps) + max_pattern_deps = ndeps; + + rule = next; + } + + free (name); +} + +/* Create a pattern rule from a suffix rule. + TARGET is the target suffix; SOURCE is the source suffix. + CMDS are the commands. + If TARGET is nil, it means the target pattern should be '(%.o)'. + If SOURCE is nil, it means there should be no deps. */ + +static void +convert_suffix_rule (const char *target, const char *source, + struct commands *cmds) +{ + const char **names, **percents; + struct dep *deps; + + names = xmalloc (sizeof (const char *)); + percents = xmalloc (sizeof (const char *)); + + if (target == 0) + { + /* Special case: TARGET being nil means we are defining a '.X.a' suffix + rule; the target pattern is always '(%.o)'. */ +#ifdef VMS + *names = strcache_add_len ("(%.obj)", 7); +#else + *names = strcache_add_len ("(%.o)", 5); +#endif + *percents = *names + 1; + } + else + { + /* Construct the target name. */ + unsigned int len = strlen (target); + char *p = alloca (1 + len + 1); + p[0] = '%'; + memcpy (p + 1, target, len + 1); + *names = strcache_add_len (p, len + 1); + *percents = *names; + } + + if (source == 0) + deps = 0; + else + { + /* Construct the dependency name. */ + unsigned int len = strlen (source); + char *p = alloca (1 + len + 1); + p[0] = '%'; + memcpy (p + 1, source, len + 1); + deps = alloc_dep (); + deps->name = strcache_add_len (p, len + 1); + } + + create_pattern_rule (names, percents, 1, 0, deps, cmds, 0); +} + +/* Convert old-style suffix rules to pattern rules. + All rules for the suffixes on the .SUFFIXES list are converted and added to + the chain of pattern rules. */ + +void +convert_to_pattern (void) +{ + struct dep *d, *d2; + char *rulename; + + /* We will compute every potential suffix rule (.x.y) from the list of + suffixes in the .SUFFIXES target's dependencies and see if it exists. + First find the longest of the suffixes. */ + + maxsuffix = 0; + for (d = suffix_file->deps; d != 0; d = d->next) + { + unsigned int l = strlen (dep_name (d)); + if (l > maxsuffix) + maxsuffix = l; + } + + /* Space to construct the suffix rule target name. */ + rulename = alloca ((maxsuffix * 2) + 1); + + for (d = suffix_file->deps; d != 0; d = d->next) + { + unsigned int slen; + + /* Make a rule that is just the suffix, with no deps or commands. + This rule exists solely to disqualify match-anything rules. */ + convert_suffix_rule (dep_name (d), 0, 0); + + if (d->file->cmds != 0) + /* Record a pattern for this suffix's null-suffix rule. */ + convert_suffix_rule ("", dep_name (d), d->file->cmds); + + /* Add every other suffix to this one and see if it exists as a + two-suffix rule. */ + slen = strlen (dep_name (d)); + memcpy (rulename, dep_name (d), slen); + + for (d2 = suffix_file->deps; d2 != 0; d2 = d2->next) + { + struct file *f; + unsigned int s2len; + + s2len = strlen (dep_name (d2)); + + /* Can't build something from itself. */ + if (slen == s2len && streq (dep_name (d), dep_name (d2))) + continue; + + memcpy (rulename + slen, dep_name (d2), s2len + 1); + f = lookup_file (rulename); + if (f == 0 || f->cmds == 0) + continue; + + if (s2len == 2 && rulename[slen] == '.' && rulename[slen + 1] == 'a') + /* A suffix rule '.X.a:' generates the pattern rule '(%.o): %.X'. + It also generates a normal '%.a: %.X' rule below. */ + convert_suffix_rule (NULL, /* Indicates '(%.o)'. */ + dep_name (d), + f->cmds); + + /* The suffix rule '.X.Y:' is converted + to the pattern rule '%.Y: %.X'. */ + convert_suffix_rule (dep_name (d2), dep_name (d), f->cmds); + } + } +} + + +/* Install the pattern rule RULE (whose fields have been filled in) at the end + of the list (so that any rules previously defined will take precedence). + If this rule duplicates a previous one (identical target and dependencies), + the old one is replaced if OVERRIDE is nonzero, otherwise this new one is + thrown out. When an old rule is replaced, the new one is put at the end of + the list. Return nonzero if RULE is used; zero if not. */ + +static int +new_pattern_rule (struct rule *rule, int override) +{ + struct rule *r, *lastrule; + unsigned int i, j; + + rule->in_use = 0; + rule->terminal = 0; + + rule->next = 0; + + /* Search for an identical rule. */ + lastrule = 0; + for (r = pattern_rules; r != 0; lastrule = r, r = r->next) + for (i = 0; i < rule->num; ++i) + { + for (j = 0; j < r->num; ++j) + if (!streq (rule->targets[i], r->targets[j])) + break; + /* If all the targets matched... */ + if (j == r->num) + { + struct dep *d, *d2; + for (d = rule->deps, d2 = r->deps; + d != 0 && d2 != 0; d = d->next, d2 = d2->next) + if (!streq (dep_name (d), dep_name (d2))) + break; + if (d == 0 && d2 == 0) + { + /* All the dependencies matched. */ + if (override) + { + /* Remove the old rule. */ + freerule (r, lastrule); + /* Install the new one. */ + if (pattern_rules == 0) + pattern_rules = rule; + else + last_pattern_rule->next = rule; + last_pattern_rule = rule; + + /* We got one. Stop looking. */ + goto matched; + } + else + { + /* The old rule stays intact. Destroy the new one. */ + freerule (rule, (struct rule *) 0); + return 0; + } + } + } + } + + matched:; + + if (r == 0) + { + /* There was no rule to replace. */ + if (pattern_rules == 0) + pattern_rules = rule; + else + last_pattern_rule->next = rule; + last_pattern_rule = rule; + } + + return 1; +} + + +/* Install an implicit pattern rule based on the three text strings + in the structure P points to. These strings come from one of + the arrays of default implicit pattern rules. + TERMINAL specifies what the 'terminal' field of the rule should be. */ + +void +install_pattern_rule (struct pspec *p, int terminal) +{ + struct rule *r; + const char *ptr; + + r = xmalloc (sizeof (struct rule)); + + r->num = 1; + r->targets = xmalloc (sizeof (const char *)); + r->suffixes = xmalloc (sizeof (const char *)); + r->lens = xmalloc (sizeof (unsigned int)); + + r->lens[0] = strlen (p->target); + r->targets[0] = p->target; + r->suffixes[0] = find_percent_cached (&r->targets[0]); + assert (r->suffixes[0] != NULL); + ++r->suffixes[0]; + + ptr = p->dep; + r->deps = PARSE_SIMPLE_SEQ ((char **)&ptr, struct dep); + + if (new_pattern_rule (r, 0)) + { + r->terminal = terminal; + r->cmds = xmalloc (sizeof (struct commands)); + r->cmds->fileinfo.filenm = 0; + r->cmds->fileinfo.lineno = 0; + /* These will all be string literals, but we malloc space for them + anyway because somebody might want to free them later. */ + r->cmds->commands = xstrdup (p->commands); + r->cmds->command_lines = 0; + r->cmds->recipe_prefix = RECIPEPREFIX_DEFAULT; + } +} + + +/* Free all the storage used in RULE and take it out of the + pattern_rules chain. LASTRULE is the rule whose next pointer + points to RULE. */ + +static void +freerule (struct rule *rule, struct rule *lastrule) +{ + struct rule *next = rule->next; + + free_dep_chain (rule->deps); + + /* MSVC erroneously warns without a cast here. */ + free ((void *)rule->targets); + free ((void *)rule->suffixes); + free (rule->lens); + + /* We can't free the storage for the commands because there + are ways that they could be in more than one place: + * If the commands came from a suffix rule, they could also be in + the 'struct file's for other suffix rules or plain targets given + on the same makefile line. + * If two suffixes that together make a two-suffix rule were each + given twice in the .SUFFIXES list, and in the proper order, two + identical pattern rules would be created and the second one would + be discarded here, but both would contain the same 'struct commands' + pointer from the 'struct file' for the suffix rule. */ + + free (rule); + + if (pattern_rules == rule) + if (lastrule != 0) + abort (); + else + pattern_rules = next; + else if (lastrule != 0) + lastrule->next = next; + if (last_pattern_rule == rule) + last_pattern_rule = lastrule; +} + +/* Create a new pattern rule with the targets in the nil-terminated array + TARGETS. TARGET_PERCENTS is an array of pointers to the % in each element + of TARGETS. N is the number of items in the array (not counting the nil + element). The new rule has dependencies DEPS and commands from COMMANDS. + It is a terminal rule if TERMINAL is nonzero. This rule overrides + identical rules with different commands if OVERRIDE is nonzero. + + The storage for TARGETS and its elements and TARGET_PERCENTS is used and + must not be freed until the rule is destroyed. */ + +void +create_pattern_rule (const char **targets, const char **target_percents, + unsigned int n, int terminal, struct dep *deps, + struct commands *commands, int override) +{ + unsigned int i; + struct rule *r = xmalloc (sizeof (struct rule)); + + r->num = n; + r->cmds = commands; + r->deps = deps; + r->targets = targets; + r->suffixes = target_percents; + r->lens = xmalloc (n * sizeof (unsigned int)); + + for (i = 0; i < n; ++i) + { + r->lens[i] = strlen (targets[i]); + assert (r->suffixes[i] != NULL); + ++r->suffixes[i]; + } + + if (new_pattern_rule (r, override)) + r->terminal = terminal; +} + +/* Print the data base of rules. */ + +static void /* Useful to call from gdb. */ +print_rule (struct rule *r) +{ + unsigned int i; + + for (i = 0; i < r->num; ++i) + { + fputs (r->targets[i], stdout); + putchar ((i + 1 == r->num) ? ':' : ' '); + } + if (r->terminal) + putchar (':'); + + print_prereqs (r->deps); + + if (r->cmds != 0) + print_commands (r->cmds); +} + +void +print_rule_data_base (void) +{ + unsigned int rules, terminal; + struct rule *r; + + puts (_("\n# Implicit Rules")); + + rules = terminal = 0; + for (r = pattern_rules; r != 0; r = r->next) + { + ++rules; + + putchar ('\n'); + print_rule (r); + + if (r->terminal) + ++terminal; + } + + if (rules == 0) + puts (_("\n# No implicit rules.")); + else + { + printf (_("\n# %u implicit rules, %u"), rules, terminal); +#ifndef NO_FLOAT + printf (" (%.1f%%)", (double) terminal / (double) rules * 100.0); +#else + { + int f = (terminal * 1000 + 5) / rules; + printf (" (%d.%d%%)", f/10, f%10); + } +#endif + puts (_(" terminal.")); + } + + if (num_pattern_rules != rules) + { + /* This can happen if a fatal error was detected while reading the + makefiles and thus count_implicit_rule_limits wasn't called yet. */ + if (num_pattern_rules != 0) + ONN (fatal, NILF, _("BUG: num_pattern_rules is wrong! %u != %u"), + num_pattern_rules, rules); + } +} |