diff options
| -rw-r--r-- | hush.c | 54 | ||||
| -rw-r--r-- | shell/hush.c | 54 |
2 files changed, 98 insertions, 10 deletions
@@ -43,6 +43,7 @@ * Brace Expansion * Tilde Expansion * fancy forms of Parameter Expansion + * aliases * Arithmetic Expansion * <(list) and >(list) Process Substitution * reserved words: case, esac, select, function @@ -54,15 +55,14 @@ * 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 @@ -70,6 +70,7 @@ * 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 * @@ -359,6 +360,9 @@ static int run_pipe_real(struct pipe *pi); 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); @@ -1001,9 +1005,20 @@ static int pipe_wait(struct pipe *pi) /* 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 @@ -1253,11 +1268,19 @@ static int run_pipe_real(struct pipe *pi) 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; @@ -1268,7 +1291,12 @@ static int run_pipe_real(struct pipe *pi) * 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; } @@ -1581,6 +1609,22 @@ static int xglob(o_string *dest, int flags, glob_t *pglob) 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. diff --git a/shell/hush.c b/shell/hush.c index 5ea9460..9f1614d 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -43,6 +43,7 @@ * Brace Expansion * Tilde Expansion * fancy forms of Parameter Expansion + * aliases * Arithmetic Expansion * <(list) and >(list) Process Substitution * reserved words: case, esac, select, function @@ -54,15 +55,14 @@ * 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 @@ -70,6 +70,7 @@ * 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 * @@ -359,6 +360,9 @@ static int run_pipe_real(struct pipe *pi); 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); @@ -1001,9 +1005,20 @@ static int pipe_wait(struct pipe *pi) /* 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 @@ -1253,11 +1268,19 @@ static int run_pipe_real(struct pipe *pi) 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; @@ -1268,7 +1291,12 @@ static int run_pipe_real(struct pipe *pi) * 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; } @@ -1581,6 +1609,22 @@ static int xglob(o_string *dest, int flags, glob_t *pglob) 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. |