Add mv

src/mv.c

@@ -0,0 +1,130 @@
+/**
+ * NAME
+ * ====
+ *     mv - move (rename) files
+ *
+ * SYNOPSIS
+ * ========
+ *     mv [-if] source_file target_file
+ *     mv [-if] source_file... target_dir
+ *     mv [--help|--version]
+ *
+ * DESCRIPTION
+ * ===========
+ *     Move files.
+ *
+ *     -i           Prompt when a file would be overwritten.
+ *     -f           Don't prompt when a file would be overwritten.
+ *
+ *     --help       Print help text and exit.
+ *     --version    Print version information and exit.
+ */
+
+#include <libgen.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include "boreutils.h"
+
+static int prompt(char *dest) {
+    char ret[2] = "-";
+    fprintf(stderr, "mv: overwrite '%s'? [y/N] ", dest);
+    fgets(ret, 2, stdin);
+
+    if (ret[0] == 'y' || ret[0] == 'Y') {
+        return 1;
+    }
+    return 0;
+}
+
+// If dest is a directory, returns `<dest>/<basename of src>`.
+// Otherwise, returns `<dest>`.
+static char *normalize_dest(char *src, char *dest) {
+    struct stat statbuf;
+    if (stat(dest, &statbuf) != 0) {
+        // `dest` doesn't exist.
+        return dest;
+    }
+
+    if (!S_ISDIR(statbuf.st_mode)) {
+        // `dest` is a file (not a directory).
+        return dest;
+    }
+
+    // Beyond this point, `dest` is known to be a directory.
+    // This means we need `<dest>/<basename of src>`.
+
+    // First, get the basename of `src`.
+    char *base_name = basename(src);
+    size_t base_name_size = strlen(base_name);
+
+    size_t dest_size = strlen(dest);
+    // <dest size> + <1 for slash> + <basename size> + <1 for null terminator>
+    char *full_dest = malloc(sizeof(char) * (dest_size + 1 + base_name_size + 1));
+    memset(full_dest, 0, dest_size + 1 + base_name_size + 1);
+
+    strncpy(full_dest, dest, dest_size + 1);
+    if (dest[dest_size - 1] != '/') {
+        full_dest[dest_size] = '/';
+        strncpy(full_dest + dest_size + 1, base_name, base_name_size + 1);
+    } else {
+        strncpy(full_dest + dest_size, base_name, base_name_size + 1);
+    }
+
+    return full_dest;
+}
+
+int main(int argc, char **argv) {
+    if (has_arg(argc, argv, "-h") || has_arg(argc, argv, "--help")) {
+        puts("Usage: mv [-if] source_file target_file");
+        puts("       mv [-if] source_file... target_dir");
+        puts("Move (rename) files.");
+        puts("-i           Prompt when a file would be overwritten.");
+        puts("-f           Don't prompt when a file would be overwritten.");
+        return 1;
+    }
+
+    if (bu_handle_version(argc, argv)) {
+        return 0;
+    }
+
+    int ret = 0;
+    int should_prompt = 0;
+    char *dest = argv[argc - 1];
+
+    int i = 1;
+    for (; i < argc; i++) {
+        if (argv[i][0] != '-') {
+            break;
+        }
+
+        for (size_t j = 1; j < strlen(argv[i]); j++) {
+            if (argv[i][j] == 'f') {
+                should_prompt = 0;
+            } else if (argv[i][j] == 'i') {
+                should_prompt = 1;
+            } else {
+                char arg[3] = {'-', argv[i][j], 0};
+                bu_invalid_argument(argv[0], arg);
+            }
+        }
+    }
+
+    for (; i < argc - 1; i++) {
+        if (should_prompt) {
+            char *normalized_dest = normalize_dest(argv[i], dest);
+            if (access(normalized_dest, F_OK) == 0) {
+                if (prompt(normalized_dest) == 0) {
+                    continue;
+                }
+            }
+        }
+
+        if (rename(argv[i], dest) == -1) {
+            perror("mv");
+            ret = 1;
+        }
+    }
+    return ret;
+}