* Brace Expansion
* Tilde Expansion
* fancy forms of Parameter Expansion
+ * aliases
* Arithmetic Expansion
* <(list) and >(list) Process Substitution
* reserved words: case, esac, select, function
* to-do:
* port selected bugfixes from post-0.49 busybox lash - done?
* finish implementing reserved words: for, while, until, do, done
+ * finish implementing local variable assignment
* change { and } from special chars to reserved words
* builtins: break, continue, eval, return, set, trap, ulimit
* test magic exec
* handle children going into background
* clean up recognition of null pipes
- * have builtin_exec set flag to avoid restore_redirects
* check setting of global_argc and global_argv
* control-C handling, probably with longjmp
- * VAR=value prefix for simple commands
* follow IFS rules more precisely, including update semantics
* figure out what to do with backslash-newline
* explain why we use signal instead of sigaction
* continuation lines, both explicit and implicit - done?
* memory leak finding and plugging - done?
* more testing, especially quoting rules and redirection
+ * document how quoting rules not precisely followed for variable assignments
* maybe change map[] to use 2-bit entries
* (eventually) remove all the printf's
*
static int globhack(const char *src, int flags, glob_t *pglob);
static int glob_needed(const char *s);
static int xglob(o_string *dest, int flags, glob_t *pglob);
+/* variable assignment: */
+static int set_local_var(const char *s);
+static int is_assignment(const char *s);
/* data structure manipulation: */
static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
static void initialize_context(struct p_context *ctx);
/* very simple version for testing */
static void pseudo_exec(struct child_prog *child)
{
- int rcode;
+ int i, rcode;
struct built_in_command *x;
if (child->argv) {
+ for (i=0; is_assignment(child->argv[i]); i++) {
+ putenv(strdup(child->argv[i]));
+ }
+ child->argv+=i; /* XXX this hack isn't so horrible, since we are about
+ to exit, and therefore don't need to keep data
+ structures consistent for free() use. */
+ /* If a variable is assigned in a forest, and nobody listens,
+ * was it ever really set?
+ */
+ if (child->argv[0] == NULL) exit(EXIT_SUCCESS);
+
/*
* Check if the command matches any of the builtins.
* Depending on context, this might be redundant. But it's
restore_redirects(squirrel);
return rcode;
}
+ for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
+ if (i!=0 && child->argv[i]==NULL) {
+ /* assignments, but no command: set the local environment */
+ for (i=0; child->argv[i]!=NULL; i++) {
+ set_local_var(child->argv[i]);
+ }
+ return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
+ }
for (x = bltins; x->cmd; x++) {
- if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ if (strcmp(child->argv[i], x->cmd) == 0 ) {
int squirrel[] = {-1, -1, -1};
int rcode;
- if (x->function == builtin_exec && child->argv[1]==NULL) {
+ if (x->function == builtin_exec && child->argv[i+1]==NULL) {
debug_printf("magic exec\n");
setup_redirects(child,NULL);
return EXIT_SUCCESS;
* Is it really safe for inline use? Experimentally,
* things seem to work with glibc. */
setup_redirects(child, squirrel);
+ for (i=0; is_assignment(child->argv[i]); i++) {
+ putenv(strdup(child->argv[i]));
+ }
+ child->argv+=i; /* XXX horrible hack */
rcode = x->function(child);
+ child->argv-=i; /* XXX restore hack so free() can work right */
restore_redirects(squirrel);
return rcode;
}
return gr;
}
+
+static int set_local_var(const char *s)
+{
+ /* when you write this, also need to update lookup_param() */
+ printf("assignment %s not handled: write me!\n",s);
+ return 0;
+}
+
+static int is_assignment(const char *s)
+{
+ if (s==NULL || !isalpha(*s)) return 0;
+ ++s;
+ while(isalnum(*s) || *s=='_') ++s;
+ return *s=='=';
+}
+
/* the src parameter allows us to peek forward to a possible &n syntax
* for file descriptor duplication, e.g., "2>&1".
* Return code is 0 normally, 1 if a syntax error is detected in src.
* Brace Expansion
* Tilde Expansion
* fancy forms of Parameter Expansion
+ * aliases
* Arithmetic Expansion
* <(list) and >(list) Process Substitution
* reserved words: case, esac, select, function
* to-do:
* port selected bugfixes from post-0.49 busybox lash - done?
* finish implementing reserved words: for, while, until, do, done
+ * finish implementing local variable assignment
* change { and } from special chars to reserved words
* builtins: break, continue, eval, return, set, trap, ulimit
* test magic exec
* handle children going into background
* clean up recognition of null pipes
- * have builtin_exec set flag to avoid restore_redirects
* check setting of global_argc and global_argv
* control-C handling, probably with longjmp
- * VAR=value prefix for simple commands
* follow IFS rules more precisely, including update semantics
* figure out what to do with backslash-newline
* explain why we use signal instead of sigaction
* continuation lines, both explicit and implicit - done?
* memory leak finding and plugging - done?
* more testing, especially quoting rules and redirection
+ * document how quoting rules not precisely followed for variable assignments
* maybe change map[] to use 2-bit entries
* (eventually) remove all the printf's
*
static int globhack(const char *src, int flags, glob_t *pglob);
static int glob_needed(const char *s);
static int xglob(o_string *dest, int flags, glob_t *pglob);
+/* variable assignment: */
+static int set_local_var(const char *s);
+static int is_assignment(const char *s);
/* data structure manipulation: */
static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
static void initialize_context(struct p_context *ctx);
/* very simple version for testing */
static void pseudo_exec(struct child_prog *child)
{
- int rcode;
+ int i, rcode;
struct built_in_command *x;
if (child->argv) {
+ for (i=0; is_assignment(child->argv[i]); i++) {
+ putenv(strdup(child->argv[i]));
+ }
+ child->argv+=i; /* XXX this hack isn't so horrible, since we are about
+ to exit, and therefore don't need to keep data
+ structures consistent for free() use. */
+ /* If a variable is assigned in a forest, and nobody listens,
+ * was it ever really set?
+ */
+ if (child->argv[0] == NULL) exit(EXIT_SUCCESS);
+
/*
* Check if the command matches any of the builtins.
* Depending on context, this might be redundant. But it's
restore_redirects(squirrel);
return rcode;
}
+ for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
+ if (i!=0 && child->argv[i]==NULL) {
+ /* assignments, but no command: set the local environment */
+ for (i=0; child->argv[i]!=NULL; i++) {
+ set_local_var(child->argv[i]);
+ }
+ return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
+ }
for (x = bltins; x->cmd; x++) {
- if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ if (strcmp(child->argv[i], x->cmd) == 0 ) {
int squirrel[] = {-1, -1, -1};
int rcode;
- if (x->function == builtin_exec && child->argv[1]==NULL) {
+ if (x->function == builtin_exec && child->argv[i+1]==NULL) {
debug_printf("magic exec\n");
setup_redirects(child,NULL);
return EXIT_SUCCESS;
* Is it really safe for inline use? Experimentally,
* things seem to work with glibc. */
setup_redirects(child, squirrel);
+ for (i=0; is_assignment(child->argv[i]); i++) {
+ putenv(strdup(child->argv[i]));
+ }
+ child->argv+=i; /* XXX horrible hack */
rcode = x->function(child);
+ child->argv-=i; /* XXX restore hack so free() can work right */
restore_redirects(squirrel);
return rcode;
}
return gr;
}
+
+static int set_local_var(const char *s)
+{
+ /* when you write this, also need to update lookup_param() */
+ printf("assignment %s not handled: write me!\n",s);
+ return 0;
+}
+
+static int is_assignment(const char *s)
+{
+ if (s==NULL || !isalpha(*s)) return 0;
+ ++s;
+ while(isalnum(*s) || *s=='_') ++s;
+ return *s=='=';
+}
+
/* the src parameter allows us to peek forward to a possible &n syntax
* for file descriptor duplication, e.g., "2>&1".
* Return code is 0 normally, 1 if a syntax error is detected in src.
projects / oweals / busybox.git / commitdiff