add completion source files

2 files changed, 70 insertions, 0 deletions

diff --git a/complete.c b/complete.c
new file mode 100644
index 0000000..a9e64f3
--- /dev/null
+++ b/complete.c
@@ -0,0 +1,69 @@
+#include <stdio.h>
+#include <stdbool.h>
+#include <string.h>
+#include <getopt.h>
+
+#include "complete.h"
+
+/*
+ * generate simple bash completion for getopt long,
+ * using "complete -W".
+ */
+#define CASE_IMAGE \
+    "    --image)\n"                                                 \
+    "        COMPREPLY=( $(compgen -f -- \"$cur\") )\n"              \
+    "        ;;\n"
+
+void complete_bash(const char *command, struct option *opts)
+{
+    bool have_image = false;
+    char opt_all[1024];
+    char opt_arg[1024];
+    int pos_all = 0;
+    int pos_arg = 0;
+    int i;
+
+    for (i = 0; opts[i].name != NULL; i++) {
+        /* options with argument completion */
+        if (strcmp(opts[i].name, "image") == 0) {
+            have_image = true;
+
+        } else if (opts[i].has_arg) {
+            /* options without argument completion */
+            pos_arg += snprintf(opt_arg+pos_arg, sizeof(opt_arg)-pos_arg,
+                                "%s--%s",
+                                pos_arg ? " | " : "",
+                                opts[i].name);
+        }
+
+        /* (long) option completion */
+        pos_all += snprintf(opt_all+pos_all, sizeof(opt_all)-pos_all,
+                            "%s--%s",
+                            pos_all ? " " : "",
+                            opts[i].name);
+    }
+    if (!pos_arg)
+        snprintf(opt_arg+pos_arg, sizeof(opt_arg)-pos_arg, "--dummy");
+
+    printf("_%s_complete()\n"
+           "{\n"
+           "    local cur prev\n"
+           "    cur=\"${COMP_WORDS[COMP_CWORD]}\"\n"
+           "    prev=\"${COMP_WORDS[COMP_CWORD-1]}\"\n"
+           "    case \"$prev\" in\n"
+           "%s"
+           "    %s)\n"
+           "        COMPREPLY=()\n"
+           "        ;;\n"
+           "    *)\n"
+           "        COMPREPLY=( $(compgen -W \"%s\" -- \"$cur\") )\n"
+           "        ;;\n"
+           "    esac\n"
+           "    return 0\n"
+           "}\n"
+           "complete -F _%s_complete %s\n"
+           "\n",
+           command,
+           have_image ? CASE_IMAGE : "",
+           opt_arg, opt_all, command, command);
+}
diff --git a/complete.h b/complete.h
new file mode 100644
index 0000000..a1fd02b
--- /dev/null
+++ b/complete.h
@@ -0,0 +1 @@
+void complete_bash(const char *command, struct option *opts);