Overhaul to use arguments instead of piping for commands

3 files changed, 83 insertions, 55 deletions

diff --git a/README.md b/README.md
index 42fe42d..e678d87 100644
--- a/README.md
+++ b/README.md
@@ -6,24 +6,23 @@
 - Highly interoperable with unix pipelines
 - Highly customizable and hackable
 - Without any build dependencies other than the C standard library (no ncurses)
-- A good proof-of-concept for making a TUI without using any libraries
+- A good proof-of-concept for making a TUI from scratch
 
 The core idea behind `bb` is that almost all actions are performed by piping
-selected files to external scripts, rather than hard-coding actions. Unix
-tools are very good at doing file management, the thing that `bb` adds is
-immediate visual feedback and rapid navigation.
-
-For example, normally on the command line, if you wanted to manually delete a
-handful of files, you would first get a listing of the files with `ls`, then
-type `rm` followed by typing out the names of the files (with some tab
-autocompletion). With `bb`, you can just launch `bb`, see all the files
-immediately, select the ones you want with a few keystrokes, and press `D` to
-delete them (or `d` for deleting with confirmation). The `D` key's behavior
-is defined in a single line of code in `config.h` to pipe the selected files
-to `xargs -0 rm -rf`. That's it! If you want to add a mapping to upload files to
-your server, you can just add a binding for `xargs scp user@example.com` or,
-if you have some complicated one-time task, you can just hit `|` and type in
-any arbitrary command and have the selected files piped to it.
+selected files to external scripts, rather than having the file manager itself
+try to anticipate and hard-code every possible user action. Unix tools are very
+good at doing file management, the thing that `bb` adds is immediate visual
+feedback and rapid navigation.
+
+For example, instead of using `ls`, then `rm` and typing out file names, you can
+just open `bb`, scroll through the list of files, select the ones you want to
+delete, and hit `D`. The `D` key's behavior is defined in a single line of code
+in `config.h` as piping the selected files to `xargs -0 rm -rf`. That's it! If
+you want to add a mapping to upload files to your server, you can just add a
+binding for `xargs -0 scp user@example.com`. Want to zip files? Add a mapping for
+`xargs -0 zip "$(printf 'Zip file: ' >/dev/tty && head -n1 /dev/tty)"` or, if
+you have some complicated one-time task, you can just hit `|` and type in any
+arbitrary command and have the selected files piped to it.
 
 ## Zero Dependencies
 
@@ -58,6 +57,9 @@ editing `config.h` and recompiling. In [suckless](https://suckless.org/) style,
 customizing means editing source code, and compilation is extremely fast.
 Key character constants are in `keys.h` and the rest of the code is in `bb.c`.
 
+If you want to get user input during a command (e.g. to get the name of a new file),
+you can use `/dev/tty` like so: `touch "$(printf 'New file: ' >/dev/tty && head -n1 /dev/tty)"`
+
 ## License
 
 `bb` is released under the MIT license. See the `LICENSE` file for full details.
diff --git a/bb.c b/bb.c
index 827707a..fa7c946 100644
--- a/bb.c
+++ b/bb.c
@@ -124,6 +124,49 @@ static void err(const char *msg, ...)
     _exit(1);
 }
 
+static int run_cmd_on_selection(bb_state_t *state, const char *cmd)
+{
+    pid_t child;
+    sig_t old_handler = signal(SIGINT, do_nothing);
+
+    if ((child = fork()) == 0) {
+        // TODO: is there a max number of args? Should this be batched?
+        char **const args = calloc(MAX(1, state->nselected) + 4, sizeof(char*));
+        int i = 0;
+        args[i++] = "sh";
+        args[i++] = "-c";
+        args[i++] = (char*)cmd;
+        args[i++] = "--";
+        entry_t *first = state->firstselected ? state->firstselected : state->files[state->cursor];
+        for (entry_t *e = first; e; e = e->next) {
+            args[i++] = e->d_name;
+        }
+        args[i] = NULL;
+
+        { // Set environment variable to track shell nesting
+            char *depthstr = getenv("BB_DEPTH");
+            int depth = depthstr ? atoi(depthstr) : 0;
+            char buf[64] = {0};
+            snprintf(buf, sizeof(buf), "BB_DEPTH=%d", depth + 1);
+            putenv(buf);
+        }
+
+        execvp("sh", args);
+        free(args);
+        err("Failed to execute command: '%s'", cmd);
+        _exit(0);
+        return -1;
+    }
+
+    if (child == -1)
+        err("Failed to fork");
+    int status;
+    waitpid(child, &status, 0);
+    signal(SIGINT, old_handler);
+    return status;
+}
+
+
 static pid_t run_cmd(int *child_out, int *child_in, const char *cmd, ...)
 {
     int child_outfds[2], child_infds[2];
@@ -885,40 +928,23 @@ static void explore(char *path, int print_dir, int print_selection, char sep)
                 for (int i = 0; bindings[i].key > 0; i++) {
                     if (key == bindings[i].key) {
                         term_move(0, height-1);
+                        writez(termfd, "\e[K");
                         struct termios cur_tios;
                         if (!(bindings[i].flags & ONSCREEN)) {
                             close_term();
                         } else {
                             tcgetattr(termfd, &cur_tios);
-                            struct termios tios;
-                            memcpy(&tios, &orig_termios, sizeof(tios));
-                            tcsetattr(termfd, TCSAFLUSH, &tios);
-                            // Show cursor
-                            writez(termfd, "\e[?25h");
+                            tcsetattr(termfd, TCSAFLUSH, &orig_termios);
+                            writez(termfd, "\e[?25h"); // Show cursor
                         }
 
-                        int scriptinfd;
-                        pid_t child;
-                        sig_t old_handler = signal(SIGINT, do_nothing);
-                        child = run_cmd(NULL, &scriptinfd, bindings[i].command);
-                        if (!(bindings[i].flags & NO_FILES)) {
-                            char sep = (bindings[i].flags & NULL_SEP) ? '\0' : '\n';
-                            if (state.nselected > 0) {
-                                write_selection(scriptinfd, state.firstselected, sep);
-                            } else if (strcmp(state.files[state.cursor]->d_name, "..") != 0) {
-                                write(scriptinfd, state.files[state.cursor]->d_name, state.files[state.cursor]->d_namlen);
-                            }
-                        }
-                        close(scriptinfd);
-                        waitpid(child, NULL, 0);
-                        signal(SIGINT, old_handler);
+                        run_cmd_on_selection(&state, bindings[i].command);
 
                         if (!(bindings[i].flags & ONSCREEN)) {
                             init_term();
                         } else {
                             tcsetattr(termfd, TCSAFLUSH, &cur_tios);
-                            // hide cursor
-                            writez(termfd, "\e[?25l");
+                            writez(termfd, "\e[?25l"); // Hide cursor
                         }
 
                         if (bindings[i].flags & CLEAR_SELECTION)
diff --git a/config.def.h b/config.def.h
index 2d308ed..e0ab01a 100644
--- a/config.def.h
+++ b/config.def.h
@@ -4,13 +4,13 @@
 #include "keys.h"
 
 #define PROG_FUZZY "fzf"
+#define PIPE_SELECTION_TO " printf '%s\\n' \"$@\" | "
+#define AND_PAUSE " && read -n1 -p '\n\e[2m...press any key to continue...\e[0m\e[?25l'"
 #define SCROLLOFF 5
 
-#define NO_FILES        (1<<0)
-#define NULL_SEP        (1<<1)
-#define REFRESH         (1<<2)
-#define CLEAR_SELECTION (1<<3)
-#define ONSCREEN        (1<<4)
+#define REFRESH         (1<<0)
+#define CLEAR_SELECTION (1<<1)
+#define ONSCREEN        (1<<2)
 
 struct {
     int key;
@@ -18,18 +18,18 @@ struct {
     int flags;
 } bindings[] = {
     // User-defined custom scripts go here:
-    {'L', "less"},
-    {'D', "xargs -0 rm -rf", CLEAR_SELECTION | REFRESH | ONSCREEN | NULL_SEP},
-    {'d', "xargs -0 -I @ sh -c 'rm -rfi @ </dev/tty'", CLEAR_SELECTION | REFRESH | ONSCREEN | NULL_SEP},
-    {'m', "xargs -0 -I @ mv -i @ . </dev/tty", CLEAR_SELECTION | REFRESH | ONSCREEN | NULL_SEP},
-    {'c', "xargs -0 -I @ cp -i @ . </dev/tty", CLEAR_SELECTION | REFRESH | ONSCREEN | NULL_SEP},
-    {'C', "xargs -0 -n1 -I @ cp @ @.copy", REFRESH | ONSCREEN | NULL_SEP},
-    {'n', "touch \"`printf '\\033[33;1mNew file:\\033[0m ' >/dev/tty && head -n1 /dev/tty`\"", ONSCREEN | REFRESH | NO_FILES},
-    {'N', "mkdir \"`printf '\\033[33;1mNew dir:\\033[0m ' >/dev/tty && head -n1 /dev/tty`\"", ONSCREEN | REFRESH | NO_FILES},
-    {'|', "sh -c \"`printf '> ' >/dev/tty && head -n1 /dev/tty`\"", REFRESH},
-    {'>', "sh -c \"`printf '> ' >/dev/tty && head -n1 /dev/tty`\"", NO_FILES | REFRESH},
-    {'r', "xargs -0 -I @ -n1 sh -c 'mv \"@\" \"`printf \"\e[1mRename \e[1;33m%%s\e[0m: \" \"@\" >&2 && head -n1 </dev/tty`\"'",
-        REFRESH | CLEAR_SELECTION | ONSCREEN | NULL_SEP},
+    {'L', PIPE_SELECTION_TO "less"},
+    {'D', "rm -rf \"$@\"", CLEAR_SELECTION | REFRESH | ONSCREEN},
+    {'d', "rm -rfi \"$@\"", CLEAR_SELECTION | REFRESH | ONSCREEN},
+    {'m', "mv -i \"$@\" .", CLEAR_SELECTION | REFRESH | ONSCREEN},
+    {'c', "cp -i \"$@\" .", CLEAR_SELECTION | REFRESH | ONSCREEN},
+    {'C', "for f; do cp \"$f\" \"$f.copy\"; done", REFRESH | ONSCREEN},
+    {'n', "read -p '\e[33;1mNew file:\e[0m ' name && touch \"$name\"", ONSCREEN | REFRESH},
+    {'N', "read -p '\e[33;1mNew dir:\e[0m ' name && mkdir \"$name\"", ONSCREEN | REFRESH},
+    {'|', "read -p \"\e[33;1m>\e[0m \" cmd && " PIPE_SELECTION_TO "$SHELL -c \"$cmd\"" AND_PAUSE, REFRESH},
+    {'>', "$SHELL", REFRESH},
+    {'r', "for f; do read -p \"Rename $f: \" renamed && mv \"$f\" \"$renamed\"; done",
+        REFRESH | CLEAR_SELECTION | ONSCREEN},
 
     // Hard-coded behaviors (these are just placeholders for the help):
     {-1, "?\t\e[0;34mOpen help menu\e[0m"},