Infrastructure, first drop of toy shell, and a bit of work on df.

7 files changed, 334 insertions, 57 deletions

diff --git a/lib/functions.c b/lib/functions.c
new file mode 100644
index 00000000..3d9a8aca
--- /dev/null
+++ b/lib/functions.c
@@ -0,0 +1,65 @@
+/* vi: set ts=4 :*/
+/* functions.c - reusable stuff.
+ *
+ * Functions with the x prefix never return failure, they either succeed or
+ * kill the program with an error message.
+ */
+
+#include "toys.h"
+
+// Die with an error message.
+void error_exit(char *msg, ...)
+{
+	va_list args;
+
+	va_start(args, msg);
+	fprintf(stderr, "%s: ", toys.which->name);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	exit(toys.exitval);
+}
+
+void strlcpy(char *dest, char *src, size_t size)
+{
+	strncpy(dest,src,size);
+	dest[size-1] = 0;
+}
+
+// Die unless we can allocate memory.
+void *xmalloc(size_t size)
+{
+	void *ret = malloc(size);
+	if (!ret) error_exit("xmalloc");
+}
+
+// Die unless we can copy this string.
+void *xstrndup(char *s, size_t n)
+{
+	void *ret = xmalloc(++n);
+	strlcpy(ret, s, n);
+	
+	return ret;
+}
+
+// Die unless we can exec argv[]
+void *xexec(char **argv)
+{
+	execvp(argv[0], argv);
+	error_exit("No %s", argv[0]);
+}
+
+// Die unless we can open/create a file, returning file descriptor.
+int xopen(char *path, int flags, int mode)
+{
+	int fd = open(path, flags, mode);
+	if (fd == -1) error_exit("No file %s\n", path);
+	return fd;
+}
+
+// Die unless we can open/create a file, returning FILE *.
+FILE *xfopen(char *path, char *mode)
+{
+	FILE *f = fopen(path, mode);
+	if (!f) error_exit("No file %s\n", path);
+	return f;
+}
diff --git a/lib/getmountlist.c b/lib/getmountlist.c
new file mode 100644
index 00000000..a2b0698d
--- /dev/null
+++ b/lib/getmountlist.c
@@ -0,0 +1,39 @@
+/* vi: set ts=4 : */
+
+#include "toys.h"
+
+#include <mntent.h>
+
+char *path_mounts = "/proc/mounts";
+
+// Get a list of mount points from /etc/mtab or /proc/mounts.  This returns
+// a reversed list, which is good for finding overmounts and such.
+
+struct mtab_list *getmountlist(int die)
+{
+	FILE *fp;
+	struct mtab_list *mtlist, *mt;
+	struct mntent me;
+	char evilbuf[2*PATH_MAX];
+
+	mtlist = 0;
+	if (!(fp = setmntent(path_mounts, "r"))) {
+		if (die) error_exit("cannot open %s", path_mounts);
+	} else {
+		while (getmntent_r(fp, &me, evilbuf, sizeof(evilbuf))) {
+			char *str;
+
+			mt = xmalloc(sizeof(struct mtab_list) + strlen(me.mnt_fsname) +
+				strlen(me.mnt_dir) + strlen(me.mnt_type) + 3);
+			mt->next = mtlist;
+			strcpy(mt->type, me.mnt_type);
+			mt->dir = mt->type + strlen(mt->type) + 1;
+			strcpy(mt->dir, me.mnt_dir);
+			mt->device = mt->dir + strlen(mt->dir) + 1;
+			mt->device = ++str;
+			strcpy(str, me.mnt_fsname);
+			mtlist = mt;
+		}
+	}
+	return mtlist;
+}
diff --git a/lib/lib.h b/lib/lib.h
new file mode 100644
index 00000000..fa24c8d5
--- /dev/null
+++ b/lib/lib.h
@@ -0,0 +1,19 @@
+/* vi: set ts=4 :*/
+
+void error_exit(char *msg, ...);
+void strlcpy(char *dest, char *src, size_t size);
+void *xmalloc(size_t size);
+void *xstrndup(char *s, size_t n);
+void *xexec(char **argv);
+int xopen(char *path, int flags, int mode);
+FILE *xfopen(char *path, char *mode);
+
+struct mtab_list {
+	struct mtab_list *next;
+	char *dir;
+	char *device;
+	char type[0];
+};
+
+struct mtab_list *getmountlist(int die);
+
diff --git a/main.c b/main.c
index 396a354c..90d80c78 100644
--- a/main.c
+++ b/main.c
@@ -11,37 +11,22 @@
 // The monster fun applet list.
 
 struct toy_list toy_list[] = {
-	{"toybox", toybox_main},
-	{"df", df_main},
-	{"toysh", toysh_main}
+	// This one is out of order on purpose.
+	{"toybox", toybox_main, 0},
+	// The rest of these are alphabetical, for binary search.
+	{"cd", cd_main, TOYFLAG_NOFORK},
+	{"df", df_main, TOYFLAG_USR|TOYFLAG_SBIN},
+	{"exit", exit_main, TOYFLAG_NOFORK},
+	{"toysh", toysh_main, TOYFLAG_BIN}
 };
 
+#define TOY_LIST_LEN (sizeof(toy_list)/sizeof(struct toy_list))
+
 // global context for this applet.
 
 struct toy_context toys;
 
-
-
-/*
-name
-main()
-struct
-usage (short long example info)
-path (/usr/sbin)
-*/
-
-int toybox_main(void)
-{
-	printf("toybox\n");
-	return 0;
-}
-
-int toysh_main(void)
-{
-	printf("toysh\n");
-}
-
-struct toy_list *find_toy_by_name(char *name)
+struct toy_list *toy_find(char *name)
 {
 	int top, bottom, middle;
 
@@ -49,40 +34,83 @@ struct toy_list *find_toy_by_name(char *name)
 	// skip the first entry, which is out of order.
 
 	if (!strncmp(name,"toybox",6)) return toy_list;
-	bottom=1;
+	bottom = 1;
 
 	// Binary search to find this applet.
 
-	top=(sizeof(toy_list)/sizeof(struct toy_list))-1;
-	for(;;) {
+	top = TOY_LIST_LEN-1;
+	for (;;) {
 		int result;
 		
-		middle=(top+bottom)/2;
-		if(middle<bottom || middle>top) return NULL;
+		middle = (top+bottom)/2;
+		if (middle<bottom || middle>top) return NULL;
 		result = strcmp(name,toy_list[middle].name);
-		if(!result) return toy_list+middle;
-		if(result<0) top=--middle;
-		else bottom=++middle;
+		if (!result) return toy_list+middle;
+		if (result<0) top=--middle;
+		else bottom = ++middle;
 	}
 }
 
-int main(int argc, char *argv[])
+// Run a toy.
+void toy_exec(char *argv[])
 {
-	char *name;
+	struct toy_list *which;
+	
+	which = toy_find(argv[0]);
+	if (!which) return;
+
+	// Free old toys contents here?
 
-	// Record command line arguments.
-	toys.argc = argc;
+	toys.which = which;
 	toys.argv = argv;
+	for (toys.argc = 0; argv[toys.argc]; toys.argc++);
+	toys.exitval = 1;
+	
+	exit(toys.which->toy_main());
+}
 
-	// Figure out which applet got called.
-	name = rindex(argv[0],'/');
-	if (!name) name = argv[0];
-	else name++;
-	toys.which = find_toy_by_name(name);
+int toybox_main(void)
+{
+	static char *toy_paths[]={"usr/","bin/","sbin/",0};
+	int i, len = 0;
+
+	if (toys.argv[1]) {
+		if (toys.argv[1][0]!='-') {
+			toy_exec(toys.argv+1);
+			error_exit("No behavior for %s\n",toys.argv[1]);
+		}
+	}
 
-	if (!toys.which) {
-		dprintf(2,"No behavior for %s\n",name);
-		return 1;
+	// Output list of applets.
+	for (i=1; i<TOY_LIST_LEN; i++) {
+		int fl = toy_list[i].flags;
+		if (fl & TOYMASK_LOCATION) {
+			if (toys.argv[1]) {
+				int j;
+				for (j=0; toy_paths[j]; j++)
+					if (fl & (1<<j)) len += printf("%s", toy_paths[j]);
+			}
+			len += printf("%s ",toy_list[i].name);
+			if (len>65) {
+				putchar('\n');
+				len=0;
+			}
+		}
 	}
-	return toys.which->toy_main();
+	putchar('\n');
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	char *name;
+
+	// Figure out which applet to call.
+	name = rindex(argv[0], '/');
+	if (!name) name=argv[0];
+	else name++;
+	argv[0] = name;
+
+	toys.argv = argv-1;
+	return toybox_main();
 }
diff --git a/toys.h b/toys.h
index ec1ad762..4bf29b70 100644
--- a/toys.h
+++ b/toys.h
@@ -6,43 +6,59 @@
  * Licensed under GPL version 2, see file LICENSE in this tarball for details.
  */
 
+#include <limits.h>
+#include <stdarg.h>
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <strings.h>
+#include <unistd.h>
 
-/*
-name
-main()
-struct
-usage (short long example info)
-path (/usr/sbin)
-*/
+#include "lib/lib.h"
 
+int cd_main(void);
+int exit_main(void);
 int toybox_main(void);
 int toysh_main(void);
 int df_main(void);
 
+#define TOYFLAG_USR      (1<<0)
+#define TOYFLAG_BIN      (1<<1)
+#define TOYFLAG_SBIN     (1<<2)
+#define TOYMASK_LOCATION ((1<<4)-1)
+
+#define TOYFLAG_NOFORK   (1<<4)
+
 extern struct toy_list {
 	char *name;
 	int (*toy_main)(void);
+	int flags;
 } toy_list[];
-struct toy_list *find_toy_by_name(char *name);
+struct toy_list *toy_find(char *name);
 
 // Global context for this applet.
 
 extern struct toy_context {
-	struct toy_list *which;
+	struct toy_list *which;  // Which entry in toy_list is this one?
+	int exitval;             // Value error_exit feeds to exit()
 	int argc;
 	char **argv;
 	char buf[4096];
 } toys;
 
+struct exit_data {;};
+struct cd_data {;};
 struct toybox_data {;};
 struct toysh_data {;};
 struct df_data {;};
 
 union toy_union {
+	struct exit_data exit;
+	struct cd_data cd;
 	struct toybox_data toybox;
 	struct toysh_data toysh;
 	struct df_data df;
 } toy;
 
+// I need a real config system.
+#define CFG_TOYS_FREE 0
diff --git a/toys/df.c b/toys/df.c
index 05c4b6c4..8901baa5 100644
--- a/toys/df.c
+++ b/toys/df.c
@@ -1,7 +1,25 @@
-/* vi: set ts=4 : */
+/* vi: set sw=4 ts=4: */
+/*
+ * df.c - report free disk space.
+ *
+ * Implemented according to SUSv3:
+ * http://www.opengroup.org/onlinepubs/009695399/utilities/df.html
+ * 
+ * usage: df [-k] [-P|-t] [file...]
+ */
+
 #include "toys.h"
 
 int df_main(void)
 {
-	printf("toys.which->name=%s\n",toys.which->name);
+	struct mtab_list *mt, *mtlist;
+
+	//int units = 512;
+	mtlist = getmountlist(1);
+	// Zap overmounts
+	for (mt = mtlist; mt; mt = mt->next) {
+		printf("type=%s dir=%s device=%s\n",mt->type,mt->dir,mt->device);
+	}
+
+	return 0;
 }
diff --git a/toys/toysh.c b/toys/toysh.c
new file mode 100644
index 00000000..77db82db
--- /dev/null
+++ b/toys/toysh.c
@@ -0,0 +1,92 @@
+/* vi: set sw=4 ts=4:
+ * 
+ * toysh - toybox shell
+ *
+ * Copyright 2006 Rob Landley <rob@landley.net>
+ *
+ * The spec for this is at:
+ * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
+ *
+ * Although things like the bash man page are good to read too.
+ */
+
+// Handle embedded NUL bytes in the command line.
+
+#include "toys.h"
+
+static int handle(char *command)
+{
+	int argc = 0, status;
+	char *argv[10], *start = command;
+	pid_t pid;
+	struct toy_list *tl;
+
+	// Parse command into argv[]
+	for (;;) {
+		char *end;
+
+		// Skip leading whitespace and detect EOL.
+		while(isspace(*start)) start++;
+		if (!*start || *start=='#') break;
+
+		// Grab next word.  (Add dequote and envvar logic here)
+		end = start;
+		while (*end && !isspace(*end)) end++;
+		argv[argc++] = xstrndup(start, end-start);
+		start=end;
+	}
+	argv[argc]=0;
+
+	if (!argc) return 0;
+
+	tl = toy_find(argv[0]);
+	// This is a bit awkward, next design cycle should clean it up.
+	// Should vfork(), move to tryspawn()?
+	pid = 0;
+	if (tl && (tl->flags & TOYFLAG_NOFORK))
+		status = tl->toy_main();
+	else {
+		pid=fork();
+		if(!pid) {
+			toy_exec(argv);
+			xexec(argv);
+		} else waitpid(pid, &status, 0);
+	}
+	while(argc) free(argv[--argc]);
+
+	return 0;
+}
+
+int cd_main(void)
+{
+	char *dest = toys.argc>1 ? toys.argv[1] : getenv("HOME");
+	if (chdir(dest)) error_exit("chdir %s",dest);
+	return 0;
+}
+
+int exit_main(void)
+{	
+	exit(toys.argc>1 ? atoi(toys.argv[1]) : 0);
+}
+
+int toysh_main(void)
+{
+	char *command=NULL;
+	FILE *f;
+
+	// TODO get_optflags(argv, "c:", &command);
+
+	f = toys.argv[1] ? xfopen(toys.argv[1], "r") : NULL;
+	if (command) handle(command);
+	else {
+		unsigned cmdlen=0;
+		for (;;) {
+			if (!f) putchar('$');
+			if (1 > getline(&command, &cmdlen, f ? : stdin)) break;
+			handle(command);
+		}
+		if (CFG_TOYS_FREE) free(command);
+	}
+		
+	return 1;
+}