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lash: "forking" applets are actually can be treated the same way as "non-forked".

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Also save a bit of space on trailing NULL array elements.
This commit is contained in:
Denis Vlasenko 2007-04-12 17:10:45 +00:00
parent 7cced6e574
commit b69f35effe
1 changed files with 27 additions and 42 deletions
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69
shell/lash.c
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@ -126,27 +126,27 @@ static int busy_loop(FILE * input);
* can change global variables in the parent shell process but they will not * can change global variables in the parent shell process but they will not
* work with pipes and redirects; 'unset foo | whatever' will not work) */ * work with pipes and redirects; 'unset foo | whatever' will not work) */
static const struct built_in_command bltins[] = { static const struct built_in_command bltins[] = {
{"bg", "Resume a job in the background", builtin_fg_bg}, {"bg" , "Resume a job in the background", builtin_fg_bg},
{"cd", "Change working directory", builtin_cd}, {"cd" , "Change working directory", builtin_cd},
{"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec}, {"exec" , "Exec command, replacing this shell with the exec'd process", builtin_exec},
{"exit", "Exit from shell()", builtin_exit}, {"exit" , "Exit from shell()", builtin_exit},
{"fg", "Bring job into the foreground", builtin_fg_bg}, {"fg" , "Bring job into the foreground", builtin_fg_bg},
{"jobs", "Lists the active jobs", builtin_jobs}, {"jobs" , "Lists the active jobs", builtin_jobs},
{"export", "Set environment variable", builtin_export}, {"export", "Set environment variable", builtin_export},
{"unset", "Unset environment variable", builtin_unset}, {"unset" , "Unset environment variable", builtin_unset},
{"read", "Input environment variable", builtin_read}, {"read" , "Input environment variable", builtin_read},
{".", "Source-in and run commands in a file", builtin_source}, {"." , "Source-in and run commands in a file", builtin_source},
/* These were "forked applets", but distinction was nuked */
/* Original comment retained: */
/* Table of forking built-in functions (things that fork cannot change global
* variables in the parent process, such as the current working directory) */
{"pwd" , "Print current directory", builtin_pwd},
{"help" , "List shell built-in commands", builtin_help},
/* to do: add ulimit */ /* to do: add ulimit */
{NULL, NULL, NULL}
}; };
/* Table of forking built-in functions (things that fork cannot change global #define VEC_SIZE(v) (sizeof(v)/sizeof(v[0]))
* variables in the parent process, such as the current working directory) */ #define VEC_LAST(v) v[VEC_SIZE(v)-1]
static struct built_in_command bltins_forking[] = {
{"pwd", "Print current directory", builtin_pwd},
{"help", "List shell built-in commands", builtin_help},
{NULL, NULL, NULL}
};
static int shell_context; /* Type prompt trigger (PS1 or PS2) */ static int shell_context; /* Type prompt trigger (PS1 or PS2) */
@ -318,12 +318,7 @@ static int builtin_help(struct child_prog ATTRIBUTE_UNUSED *dummy)
printf("\nBuilt-in commands:\n" printf("\nBuilt-in commands:\n"
"-------------------\n"); "-------------------\n");
for (x = bltins; x->cmd; x++) { for (x = bltins; x <= &VEC_LAST(bltins); x++) {
if (x->descr == NULL)
continue;
printf("%s\t%s\n", x->cmd, x->descr);
}
for (x = bltins_forking; x->cmd; x++) {
if (x->descr == NULL) if (x->descr == NULL)
continue; continue;
printf("%s\t%s\n", x->cmd, x->descr); printf("%s\t%s\n", x->cmd, x->descr);
@ -963,7 +958,7 @@ static int parse_command(char **command_ptr, struct job *job, int *inbg)
*src == ']') *buf++ = '\\'; *src == ']') *buf++ = '\\';
*buf++ = *src; *buf++ = *src;
} else if (isspace(*src)) { } else if (isspace(*src)) {
if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE) { if (*prog->argv[argc_l] || (flag & LASH_OPT_SAW_QUOTE)) {
buf++, argc_l++; buf++, argc_l++;
/* +1 here leaves room for the NULL which ends argv */ /* +1 here leaves room for the NULL which ends argv */
if ((argc_l + 1) == argv_alloced) { if ((argc_l + 1) == argv_alloced) {
@ -1143,19 +1138,13 @@ static int pseudo_exec(struct child_prog *child)
* easier to waste a few CPU cycles than it is to figure out * easier to waste a few CPU cycles than it is to figure out
* if this is one of those cases. * if this is one of those cases.
*/ */
for (x = bltins; x->cmd; x++) { /* Check if the command matches any of the forking builtins. */
for (x = bltins; x <= &VEC_LAST(bltins); x++) {
if (strcmp(child->argv[0], x->cmd) == 0) { if (strcmp(child->argv[0], x->cmd) == 0) {
_exit(x->function(child)); _exit(x->function(child));
} }
} }
/* Check if the command matches any of the forking builtins. */
for (x = bltins_forking; x->cmd; x++) {
if (strcmp(child->argv[0], x->cmd) == 0) {
applet_name = x->cmd;
_exit(x->function(child));
}
}
/* Check if the command matches any busybox internal /* Check if the command matches any busybox internal
* commands ("applets") here. Following discussions from * commands ("applets") here. Following discussions from
@ -1237,23 +1226,19 @@ static int run_command(struct job *newjob, int inbg, int outpipe[2])
const struct built_in_command *x; const struct built_in_command *x;
struct child_prog *child; struct child_prog *child;
nextin = 0, nextout = 1; nextin = 0;
for (i = 0; i < newjob->num_progs; i++) { for (i = 0; i < newjob->num_progs; i++) {
child = &(newjob->progs[i]); child = &(newjob->progs[i]);
nextout = 1;
if ((i + 1) < newjob->num_progs) { if ((i + 1) < newjob->num_progs) {
if (pipe(pipefds) < 0) if (pipe(pipefds) < 0)
bb_perror_msg_and_die("pipe"); bb_perror_msg_and_die("pipe");
nextout = pipefds[1]; nextout = pipefds[1];
} else { } else if (outpipe[1] != -1) {
if (outpipe[1] != -1) { nextout = outpipe[1];
nextout = outpipe[1];
} else {
nextout = 1;
}
} }
/* Check if the command matches any non-forking builtins, /* Check if the command matches any non-forking builtins,
* but only if this is a simple command. * but only if this is a simple command.
* Non-forking builtins within pipes have to fork anyway, * Non-forking builtins within pipes have to fork anyway,
@ -1267,7 +1252,7 @@ static int run_command(struct job *newjob, int inbg, int outpipe[2])
return builtin_export(child); return builtin_export(child);
} }
for (x = bltins; x->cmd; x++) { for (x = bltins; x <= &VEC_LAST(bltins); x++) {
if (strcmp(child->argv[0], x->cmd) == 0) { if (strcmp(child->argv[0], x->cmd) == 0) {
int rcode; int rcode;
int squirrel[] = {-1, -1, -1}; int squirrel[] = {-1, -1, -1};
@ -1279,7 +1264,7 @@ static int run_command(struct job *newjob, int inbg, int outpipe[2])
} }
} }
#if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__) #if BB_MMU
child->pid = fork(); child->pid = fork();
#else #else
child->pid = vfork(); child->pid = vfork();