1 files changed, 193 insertions, 0 deletions
diff --git a/src/instance.c b/src/instance.c
new file mode 100644
index 0000000..20c0f59
--- /dev/null
+++ b/src/instance.c
@@ -0,0 +1,193 @@
+#include "instance.h"
+#include "l2su.h"
+#include "uuid/uuid.h"
+
+#include <stdlib.h>
+#include <jansson.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+
+#include <errno.h>
+
+int l2_instance__load_all_from_object(json_t *obj);
+json_t *l2_instance__save_all_to_object(void);
+
+/* da main functionality */
+
+int l2_instance_load_all(void)
+{
+  /* open + openat because I am too lazy to concatenate the path with the filename */
+  int instfd = l2_launcher_open_config("instance.json", O_RDONLY, 0);
+  if (instfd < 0) {
+    return errno == ENOENT ? INSTANCE_SUCCESS : INSTANCE_ERRNO;
+  }
+
+  json_error_t jserr;
+  json_t *js = json_loadfd(instfd, JSON_REJECT_DUPLICATES, &jserr);
+
+  if (!js) {
+    fprintf(stderr, "error: JSON error in instance.json: %s (%s:%d:%d)\n", jserr.text, jserr.source, jserr.line, jserr.column);
+    return INSTANCE_EJSON;
+  }
+
+  if (!json_is_object(js)) {
+    fprintf(stderr, "error: instances.json value is not an object (is actually %d)\n", json_typeof(js));
+    json_decref(js);
+    return INSTANCE_EFORMAT;
+  }
+
+  int res = l2_instance__load_all_from_object(js);
+  json_decref(js);
+  return res;
+}
+
+int l2_instance_save_all(void)
+{
+  json_t *js = NULL;
+  int instfd = l2_launcher_open_config("instance.json", O_WRONLY | O_CREAT, 0644);
+  if (instfd < 0) return INSTANCE_ERRNO;
+
+  int retval = INSTANCE_SUCCESS;
+
+  js = l2_instance__save_all_to_object();
+  if (!js) {
+    retval = INSTANCE_EJSON;
+    goto save_done;
+  }
+
+  if (json_dumpfd(js, instfd, JSON_INDENT(4)) < 0) {
+    retval = INSTANCE_EJSON;
+  }
+
+save_done:
+  close(instfd);
+  json_decref(js);
+  return retval;
+}
+
+/* public utilities */
+
+int l2_instance_add_instance(const struct l2_instance *inst)
+{
+  char *path = strdup(inst->path);
+  if (!path) return INSTANCE_ERRNO;
+  
+  char *name = strdup(inst->name);
+  if (!name) {
+    free(path);
+    return INSTANCE_ERRNO;
+  }
+
+  struct l2_instance *newinst = calloc(1, sizeof(struct l2_instance));
+  if (!newinst) {
+    free(path);
+    free(name);
+    return INSTANCE_ERRNO;
+  }
+
+  newinst->uuid = inst->uuid;
+  newinst->path = path;
+  newinst->name = name;
+
+  if (l2_state.instance_head && l2_state.instance_tail) {
+    l2_state.instance_tail->next = newinst;
+    newinst->prev = l2_state.instance_tail;
+    l2_state.instance_tail = newinst;
+  } else {
+    l2_state.instance_head = l2_state.instance_tail = newinst;
+  }
+
+  return INSTANCE_SUCCESS;
+}
+
+int l2_instance_del_instance(struct l2_instance *inst)
+{
+  if (inst->next) {
+    inst->next->prev = inst->prev;
+  } else {
+    l2_state.instance_tail = inst->prev;
+  }
+
+  if (inst->prev) {
+    inst->prev->next = inst->next;
+  } else {
+    l2_state.instance_head = inst->next;
+  }
+
+  return INSTANCE_SUCCESS;
+}
+
+/* internal utilities */
+
+int l2_instance__load_all_from_object(json_t *obj)
+{
+  const char *key;
+  json_t *val;
+  json_t *tempval;
+  int res;
+
+  struct l2_instance inst;
+
+  json_object_foreach(obj, key, val) {
+    if (!json_is_object(val)) {
+      return INSTANCE_EFORMAT;
+    }
+
+    if (!l2_uuid_from_string(&inst.uuid, key)) {
+      return INSTANCE_EFORMAT; /* invalid UUID */
+    }
+
+    tempval = json_object_get(val, "name");
+    if (!json_is_string(tempval)) {
+      return INSTANCE_EFORMAT;
+    }
+
+    /* it's okay to discard const here because add_instance duplicates the string */
+    inst.name = (char *)json_string_value(tempval);
+
+    tempval = json_object_get(val, "path");
+    if (!json_is_string(tempval)) {
+      return INSTANCE_EFORMAT;
+    }
+
+    inst.path = (char *)json_string_value(tempval);
+
+    if ((res = l2_instance_add_instance(&inst)) != INSTANCE_SUCCESS) {
+      return res;
+    }
+  }
+
+  return INSTANCE_SUCCESS;
+}
+
+json_t *l2_instance__save_all_to_object(void)
+{
+  json_t *obj = json_object();
+  json_t *jinst;
+  if (!obj) return NULL;
+
+  char uuidbuf[UUID_STRLEN + 1];
+
+  for (struct l2_instance *inst = l2_state.instance_head; inst; inst = inst->next) {
+    l2_uuid_to_string(&inst->uuid, uuidbuf);
+    if (json_object_set_new(obj, uuidbuf, jinst = json_object()) < 0) {
+      goto save_err; /* jinst is decref'd anyway (undocumented) */
+    }
+
+    if (json_object_set_new(jinst, "name", json_string(inst->name)) < 0) {
+      goto save_err;
+    }
+
+    if (json_object_set_new(jinst, "path", json_string(inst->path)) < 0) {
+      goto save_err;
+    }
+  }
+
+  return obj;
+
+save_err:
+  json_decref(obj);
+  return NULL;
+}