--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (C) 2018 Masahiro Yamada <yamada.masahiro@socionext.com>
+
+#include <ctype.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "list.h"
+#include "lkc.h"
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+static char *expand_string_with_args(const char *in, int argc, char *argv[]);
+
+static void __attribute__((noreturn)) pperror(const char *format, ...)
+{
+ va_list ap;
+
+ fprintf(stderr, "%s:%d: ", current_file->name, yylineno);
+ va_start(ap, format);
+ vfprintf(stderr, format, ap);
+ va_end(ap);
+ fprintf(stderr, "\n");
+
+ exit(1);
+}
+
+/*
+ * Environment variables
+ */
+static LIST_HEAD(env_list);
+
+struct env {
+ char *name;
+ char *value;
+ struct list_head node;
+};
+
+static void env_add(const char *name, const char *value)
+{
+ struct env *e;
+
+ e = xmalloc(sizeof(*e));
+ e->name = xstrdup(name);
+ e->value = xstrdup(value);
+
+ list_add_tail(&e->node, &env_list);
+}
+
+static void env_del(struct env *e)
+{
+ list_del(&e->node);
+ free(e->name);
+ free(e->value);
+ free(e);
+}
+
+/* The returned pointer must be freed when done */
+static char *env_expand(const char *name)
+{
+ struct env *e;
+ const char *value;
+
+ if (!*name)
+ return NULL;
+
+ list_for_each_entry(e, &env_list, node) {
+ if (!strcmp(name, e->name))
+ return xstrdup(e->value);
+ }
+
+ value = getenv(name);
+ if (!value)
+ return NULL;
+
+ /*
+ * We need to remember all referenced environment variables.
+ * They will be written out to include/config/auto.conf.cmd
+ */
+ env_add(name, value);
+
+ return xstrdup(value);
+}
+
+void env_write_dep(FILE *f, const char *autoconfig_name)
+{
+ struct env *e, *tmp;
+
+ list_for_each_entry_safe(e, tmp, &env_list, node) {
+ fprintf(f, "ifneq \"$(%s)\" \"%s\"\n", e->name, e->value);
+ fprintf(f, "%s: FORCE\n", autoconfig_name);
+ fprintf(f, "endif\n");
+ env_del(e);
+ }
+}
+
+/*
+ * Built-in functions
+ */
+struct function {
+ const char *name;
+ unsigned int min_args;
+ unsigned int max_args;
+ char *(*func)(int argc, char *argv[]);
+};
+
+static char *do_error_if(int argc, char *argv[])
+{
+ if (!strcmp(argv[0], "y"))
+ pperror("%s", argv[1]);
+
+ return NULL;
+}
+
+static char *do_filename(int argc, char *argv[])
+{
+ return xstrdup(current_file->name);
+}
+
+static char *do_info(int argc, char *argv[])
+{
+ printf("%s\n", argv[0]);
+
+ return xstrdup("");
+}
+
+static char *do_lineno(int argc, char *argv[])
+{
+ char buf[16];
+
+ sprintf(buf, "%d", yylineno);
+
+ return xstrdup(buf);
+}
+
+static char *do_shell(int argc, char *argv[])
+{
+ FILE *p;
+ char buf[256];
+ char *cmd;
+ size_t nread;
+ int i;
+
+ cmd = argv[0];
+
+ p = popen(cmd, "r");
+ if (!p) {
+ perror(cmd);
+ exit(1);
+ }
+
+ nread = fread(buf, 1, sizeof(buf), p);
+ if (nread == sizeof(buf))
+ nread--;
+
+ /* remove trailing new lines */
+ while (nread > 0 && buf[nread - 1] == '\n')
+ nread--;
+
+ buf[nread] = 0;
+
+ /* replace a new line with a space */
+ for (i = 0; i < nread; i++) {
+ if (buf[i] == '\n')
+ buf[i] = ' ';
+ }
+
+ if (pclose(p) == -1) {
+ perror(cmd);
+ exit(1);
+ }
+
+ return xstrdup(buf);
+}
+
+static char *do_warning_if(int argc, char *argv[])
+{
+ if (!strcmp(argv[0], "y"))
+ fprintf(stderr, "%s:%d: %s\n",
+ current_file->name, yylineno, argv[1]);
+
+ return xstrdup("");
+}
+
+static const struct function function_table[] = {
+ /* Name MIN MAX Function */
+ { "error-if", 2, 2, do_error_if },
+ { "filename", 0, 0, do_filename },
+ { "info", 1, 1, do_info },
+ { "lineno", 0, 0, do_lineno },
+ { "shell", 1, 1, do_shell },
+ { "warning-if", 2, 2, do_warning_if },
+};
+
+#define FUNCTION_MAX_ARGS 16
+
+static char *function_expand(const char *name, int argc, char *argv[])
+{
+ const struct function *f;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(function_table); i++) {
+ f = &function_table[i];
+ if (strcmp(f->name, name))
+ continue;
+
+ if (argc < f->min_args)
+ pperror("too few function arguments passed to '%s'",
+ name);
+
+ if (argc > f->max_args)
+ pperror("too many function arguments passed to '%s'",
+ name);
+
+ return f->func(argc, argv);
+ }
+
+ return NULL;
+}
+
+/*
+ * Variables (and user-defined functions)
+ */
+static LIST_HEAD(variable_list);
+
+struct variable {
+ char *name;
+ char *value;
+ enum variable_flavor flavor;
+ int exp_count;
+ struct list_head node;
+};
+
+static struct variable *variable_lookup(const char *name)
+{
+ struct variable *v;
+
+ list_for_each_entry(v, &variable_list, node) {
+ if (!strcmp(name, v->name))
+ return v;
+ }
+
+ return NULL;
+}
+
+static char *variable_expand(const char *name, int argc, char *argv[])
+{
+ struct variable *v;
+ char *res;
+
+ v = variable_lookup(name);
+ if (!v)
+ return NULL;
+
+ if (argc == 0 && v->exp_count)
+ pperror("Recursive variable '%s' references itself (eventually)",
+ name);
+
+ if (v->exp_count > 1000)
+ pperror("Too deep recursive expansion");
+
+ v->exp_count++;
+
+ if (v->flavor == VAR_RECURSIVE)
+ res = expand_string_with_args(v->value, argc, argv);
+ else
+ res = xstrdup(v->value);
+
+ v->exp_count--;
+
+ return res;
+}
+
+void variable_add(const char *name, const char *value,
+ enum variable_flavor flavor)
+{
+ struct variable *v;
+ char *new_value;
+ bool append = false;
+
+ v = variable_lookup(name);
+ if (v) {
+ /* For defined variables, += inherits the existing flavor */
+ if (flavor == VAR_APPEND) {
+ flavor = v->flavor;
+ append = true;
+ } else {
+ free(v->value);
+ }
+ } else {
+ /* For undefined variables, += assumes the recursive flavor */
+ if (flavor == VAR_APPEND)
+ flavor = VAR_RECURSIVE;
+
+ v = xmalloc(sizeof(*v));
+ v->name = xstrdup(name);
+ v->exp_count = 0;
+ list_add_tail(&v->node, &variable_list);
+ }
+
+ v->flavor = flavor;
+
+ if (flavor == VAR_SIMPLE)
+ new_value = expand_string(value);
+ else
+ new_value = xstrdup(value);
+
+ if (append) {
+ v->value = xrealloc(v->value,
+ strlen(v->value) + strlen(new_value) + 2);
+ strcat(v->value, " ");
+ strcat(v->value, new_value);
+ free(new_value);
+ } else {
+ v->value = new_value;
+ }
+}
+
+static void variable_del(struct variable *v)
+{
+ list_del(&v->node);
+ free(v->name);
+ free(v->value);
+ free(v);
+}
+
+void variable_all_del(void)
+{
+ struct variable *v, *tmp;
+
+ list_for_each_entry_safe(v, tmp, &variable_list, node)
+ variable_del(v);
+}
+
+/*
+ * Evaluate a clause with arguments. argc/argv are arguments from the upper
+ * function call.
+ *
+ * Returned string must be freed when done
+ */
+static char *eval_clause(const char *str, size_t len, int argc, char *argv[])
+{
+ char *tmp, *name, *res, *endptr, *prev, *p;
+ int new_argc = 0;
+ char *new_argv[FUNCTION_MAX_ARGS];
+ int nest = 0;
+ int i;
+ unsigned long n;
+
+ tmp = xstrndup(str, len);
+
+ /*
+ * If variable name is '1', '2', etc. It is generally an argument
+ * from a user-function call (i.e. local-scope variable). If not
+ * available, then look-up global-scope variables.
+ */
+ n = strtoul(tmp, &endptr, 10);
+ if (!*endptr && n > 0 && n <= argc) {
+ res = xstrdup(argv[n - 1]);
+ goto free_tmp;
+ }
+
+ prev = p = tmp;
+
+ /*
+ * Split into tokens
+ * The function name and arguments are separated by a comma.
+ * For example, if the function call is like this:
+ * $(foo,$(x),$(y))
+ *
+ * The input string for this helper should be:
+ * foo,$(x),$(y)
+ *
+ * and split into:
+ * new_argv[0] = 'foo'
+ * new_argv[1] = '$(x)'
+ * new_argv[2] = '$(y)'
+ */
+ while (*p) {
+ if (nest == 0 && *p == ',') {
+ *p = 0;
+ if (new_argc >= FUNCTION_MAX_ARGS)
+ pperror("too many function arguments");
+ new_argv[new_argc++] = prev;
+ prev = p + 1;
+ } else if (*p == '(') {
+ nest++;
+ } else if (*p == ')') {
+ nest--;
+ }
+
+ p++;
+ }
+ new_argv[new_argc++] = prev;
+
+ /*
+ * Shift arguments
+ * new_argv[0] represents a function name or a variable name. Put it
+ * into 'name', then shift the rest of the arguments. This simplifies
+ * 'const' handling.
+ */
+ name = expand_string_with_args(new_argv[0], argc, argv);
+ new_argc--;
+ for (i = 0; i < new_argc; i++)
+ new_argv[i] = expand_string_with_args(new_argv[i + 1],
+ argc, argv);
+
+ /* Search for variables */
+ res = variable_expand(name, new_argc, new_argv);
+ if (res)
+ goto free;
+
+ /* Look for built-in functions */
+ res = function_expand(name, new_argc, new_argv);
+ if (res)
+ goto free;
+
+ /* Last, try environment variable */
+ if (new_argc == 0) {
+ res = env_expand(name);
+ if (res)
+ goto free;
+ }
+
+ res = xstrdup("");
+free:
+ for (i = 0; i < new_argc; i++)
+ free(new_argv[i]);
+ free(name);
+free_tmp:
+ free(tmp);
+
+ return res;
+}
+
+/*
+ * Expand a string that follows '$'
+ *
+ * For example, if the input string is
+ * ($(FOO)$($(BAR)))$(BAZ)
+ * this helper evaluates
+ * $($(FOO)$($(BAR)))
+ * and returns a new string containing the expansion (note that the string is
+ * recursively expanded), also advancing 'str' to point to the next character
+ * after the corresponding closing parenthesis, in this case, *str will be
+ * $(BAR)
+ */
+static char *expand_dollar_with_args(const char **str, int argc, char *argv[])
+{
+ const char *p = *str;
+ const char *q;
+ int nest = 0;
+
+ /*
+ * In Kconfig, variable/function references always start with "$(".
+ * Neither single-letter variables as in $A nor curly braces as in ${CC}
+ * are supported. '$' not followed by '(' loses its special meaning.
+ */
+ if (*p != '(') {
+ *str = p;
+ return xstrdup("$");
+ }
+
+ p++;
+ q = p;
+ while (*q) {
+ if (*q == '(') {
+ nest++;
+ } else if (*q == ')') {
+ if (nest-- == 0)
+ break;
+ }
+ q++;
+ }
+
+ if (!*q)
+ pperror("unterminated reference to '%s': missing ')'", p);
+
+ /* Advance 'str' to after the expanded initial portion of the string */
+ *str = q + 1;
+
+ return eval_clause(p, q - p, argc, argv);
+}
+
+char *expand_dollar(const char **str)
+{
+ return expand_dollar_with_args(str, 0, NULL);
+}
+
+static char *__expand_string(const char **str, bool (*is_end)(char c),
+ int argc, char *argv[])
+{
+ const char *in, *p;
+ char *expansion, *out;
+ size_t in_len, out_len;
+
+ out = xmalloc(1);
+ *out = 0;
+ out_len = 1;
+
+ p = in = *str;
+
+ while (1) {
+ if (*p == '$') {
+ in_len = p - in;
+ p++;
+ expansion = expand_dollar_with_args(&p, argc, argv);
+ out_len += in_len + strlen(expansion);
+ out = xrealloc(out, out_len);
+ strncat(out, in, in_len);
+ strcat(out, expansion);
+ free(expansion);
+ in = p;
+ continue;
+ }
+
+ if (is_end(*p))
+ break;
+
+ p++;
+ }
+
+ in_len = p - in;
+ out_len += in_len;
+ out = xrealloc(out, out_len);
+ strncat(out, in, in_len);
+
+ /* Advance 'str' to the end character */
+ *str = p;
+
+ return out;
+}
+
+static bool is_end_of_str(char c)
+{
+ return !c;
+}
+
+/*
+ * Expand variables and functions in the given string. Undefined variables
+ * expand to an empty string.
+ * The returned string must be freed when done.
+ */
+static char *expand_string_with_args(const char *in, int argc, char *argv[])
+{
+ return __expand_string(&in, is_end_of_str, argc, argv);
+}
+
+char *expand_string(const char *in)
+{
+ return expand_string_with_args(in, 0, NULL);
+}
+
+static bool is_end_of_token(char c)
+{
+ return !(isalnum(c) || c == '_' || c == '-');
+}
+
+/*
+ * Expand variables in a token. The parsing stops when a token separater
+ * (in most cases, it is a whitespace) is encountered. 'str' is updated to
+ * point to the next character.
+ *
+ * The returned string must be freed when done.
+ */
+char *expand_one_token(const char **str)
+{
+ return __expand_string(str, is_end_of_token, 0, NULL);
+}
projects / linux-libre-firmware.git / blobdiff