Next drop of toysh, plus more infratructure.

1 files changed, 151 insertions, 29 deletions

diff --git a/toys/toysh.c b/toys/toysh.c
index 77db82db..1d792f1f 100644
--- a/toys/toysh.c
+++ b/toys/toysh.c
@@ -14,47 +14,169 @@
 
 #include "toys.h"
 
-static int handle(char *command)
+// A single executable, its arguments, and other information we know about it.
+#define TOYSH_FLAG_EXIT    1
+#define TOYSH_FLAG_SUSPEND 2
+#define TOYSH_FLAG_PIPE    4
+#define TOYSH_FLAG_AND     8
+#define TOYSH_FLAG_OR      16
+#define TOYSH_FLAG_AMP     32
+#define TOYSH_FLAG_SEMI    64
+#define TOYSH_FLAG_PAREN   128
+
+// What we know about a single process.
+struct command {
+	struct command *next;
+	int flags;              // exit, suspend, && ||
+	int pid;                // pid (or exit code)
+	int argc;
+	char *argv[0];
+};
+
+// A collection of processes piped into/waiting on each other.
+struct pipeline {
+	struct pipeline *next;
+	int job_id;
+	struct command *cmd;
+	char *cmdline;         // Unparsed line for display purposes
+	int cmdlinelen;        // How long is cmdline?
+};
+
+// Parse one word from the command line, appending one or more argv[] entries
+// to struct command.  Handles environment variable substitution and
+// substrings.  Returns pointer to next used byte, or NULL if it
+// hit an ending token.
+static char *parse_word(char *start, struct command **cmd)
 {
-	int argc = 0, status;
-	char *argv[10], *start = command;
-	pid_t pid;
-	struct toy_list *tl;
+	char *end;
+
+	// Detect end of line (and truncate line at comment)
+	if (CFG_TOYSH_PIPES && strchr("><&|(;", *start)) return 0;
+
+	// Grab next word.  (Add dequote and envvar logic here)
+	end = start;
+	while (*end && !isspace(*end)) end++;
+	(*cmd)->argv[(*cmd)->argc++] = xstrndup(start, end-start);
+
+	// Allocate more space if there's no room for NULL terminator.
+
+	if (!((*cmd)->argc & 7))
+		xrealloc((void **)cmd,
+				sizeof(struct command) + ((*cmd)->argc+8)*sizeof(char *));
+	(*cmd)->argv[(*cmd)->argc] = 0;
+	return end;
+}
+
+// Parse a line of text into a pipeline.
+// Returns a pointer to the next line.
+
+static char *parse_pipeline(char *cmdline, struct pipeline *line)
+{
+	struct command **cmd = &(line->cmd);
+	char *start = line->cmdline = cmdline;
 
+	if (!cmdline) return 0;
+
+	if (CFG_TOYSH_JOBCTL) line->cmdline = cmdline;
+		
 	// Parse command into argv[]
 	for (;;) {
 		char *end;
+		
+		// Skip leading whitespace and detect end of line.
+		while (isspace(*start)) start++;
+		if (!*start || *start=='#') {
+			if (CFG_TOYSH_JOBCTL) line->cmdlinelen = start-cmdline;
+			return 0;
+		}
+
+		// Allocate next command structure if necessary
+		if (!*cmd) *cmd = xzalloc(sizeof(struct command)+8*sizeof(char *));
 
-		// Skip leading whitespace and detect EOL.
-		while(isspace(*start)) start++;
-		if (!*start || *start=='#') break;
+		// Parse next argument and add the results to argv[]
+		end = parse_word(start, cmd);
 
-		// Grab next word.  (Add dequote and envvar logic here)
-		end = start;
-		while (*end && !isspace(*end)) end++;
-		argv[argc++] = xstrndup(start, end-start);
-		start=end;
+		// If we hit the end of this command, how did it end?
+		if (!end) {
+			if (CFG_TOYSH_PIPES && *start) {
+				if (*start==';') {
+					start++;
+					break;
+				}
+				// handle | & < > >> << || &&
+			}
+			break;
+		}
+		start = end;
 	}
-	argv[argc]=0;
 
-	if (!argc) return 0;
+	if (CFG_TOYSH_JOBCTL) line->cmdlinelen = start-cmdline;
 
-	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);
+	return start;
+}
+
+// Execute the commands in a pipeline
+static void run_pipeline(struct pipeline *line)
+{
+	struct toy_list *tl;
+	struct command *cmd = line->cmd;
+	if (!cmd || !cmd->argc) return;
+
+	tl = toy_find(cmd->argv[0]);
+	// Is this command a builtin that should run in this process?
+	if (tl && (tl->flags & TOYFLAG_NOFORK)) {
+		struct toy_list *which = toys.which;
+		char **argv = toys.argv;
+
+		toy_init(tl, cmd->argv);
+		cmd->pid = tl->toy_main();
+		toy_init(which, argv);
+	} else {
+		int status;
+
+		cmd->pid = vfork();
+		if (!cmd->pid) xexec(cmd->argv);
+		else waitpid(cmd->pid, &status, 0);
+
+		if (CFG_TOYSH_FLOWCTL || CFG_TOYSH_PIPES) {
+			if (WIFEXITED(status)) cmd->pid = WEXITSTATUS(status);
+			if (WIFSIGNALED(status)) cmd->pid = WTERMSIG(status);
+		}
 	}
-	while(argc) free(argv[--argc]);
 
-	return 0;
+	return;
+}
+
+// Free the contents of a command structure
+static void free_cmd(void *data)
+{
+	struct command *cmd=(struct command *)data;
+
+	while(cmd->argc) free(cmd->argv[--cmd->argc]);
+}
+
+
+// Parse a command line and do what it says to do.
+static void handle(char *command)
+{
+	struct pipeline line;
+	char *start = command;
+
+	// Loop through commands in this line
+
+	for (;;) {
+
+		// Parse a group of connected commands
+
+		memset(&line,0,sizeof(struct pipeline));
+		start = parse_pipeline(start, &line);
+		if (!line.cmd) break;
+
+		// Run those commands
+
+		run_pipeline(&line);
+		llist_free(line.cmd, free_cmd);
+	}
 }
 
 int cd_main(void)