+ filelist.[ch]

src/filelist.c

@@ -0,0 +1,149 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor Boston, MA 02110-1301,  USA
+ */
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "filelist.h"
+
+#define FREE(x) free((x)), (x) = NULL;
+
+static const int grow_step = 100;
+
+static bool
+filelist_grow(filelist_t *list, int size) {
+  char **p = NULL;
+
+  assert(list != NULL);
+
+  if (size <= 0)
+    return false;
+  if (size <= list->caps)
+    return false;
+
+  if ((p = realloc(list->files, size * sizeof(char *))) == NULL)
+    return false;
+
+  list->files = p,
+  list->caps  = size;
+
+  return true;
+}
+
+filelist_t *
+filelist_create(int size) {
+  filelist_t *tmp = NULL;
+
+  if ((tmp = calloc(1, sizeof(filelist_t))) == NULL)
+    return NULL;
+
+  if (size == 0)
+    return tmp;
+
+  if (!filelist_grow(tmp, size))
+    FREE(tmp);
+
+  return tmp;
+}
+
+const char *
+filelist_get(filelist_t *list, int num) {
+  assert(list != NULL);
+
+  if (num < 1 || num > list->size)
+    return NULL;
+
+  return list->files[num - 1];
+}
+
+int
+filelist_append(filelist_t *list, const char *path) {
+  assert(list != NULL);
+
+  if (list->size >= list->caps) {
+    int newcaps = list->caps ? list->caps * 2 : grow_step;
+    if (!filelist_grow(list, newcaps))
+      return 0;
+  }
+
+  if ((list->files[list->size] = strdup(path)) == NULL)
+    return 0;
+
+  list->size++;
+  return list->size;
+}
+
+bool
+filelist_set(filelist_t *list, int num, const char *path) {
+  char *p = NULL;
+  assert(list != NULL);
+
+  if (num-- < 1)
+    return false;
+
+  if (num >= list->caps) {
+    if (!filelist_grow(list, num + grow_step))
+      return false;
+  }
+
+  if (path == NULL) {
+    FREE(list->files[num]);
+    return true;
+  }
+
+  if ((p = strdup(path)) == NULL)
+    return false;
+
+  FREE(list->files[num]);
+  list->files[num] = p;
+  return true;
+}
+
+void
+filelist_del(filelist_t *list, int num) {
+  assert(list != NULL);
+
+  if (num-- < 1)
+    return;
+  if (num > list->size)
+    return;
+  if (list->files[num] == NULL)
+    return;
+  FREE(list->files[num]);
+  if ((num + 1) == list->size)
+    list->size--;
+  return;
+}
+
+void
+filelist_free(filelist_t *list) {
+  assert(list != NULL);
+
+  for (int i = 0; i < list->size; i++) {
+    if (list->files[i] == NULL)
+      continue;
+    FREE(list->files[i]);
+  }
+  FREE(list->files);
+  list->size = 0;
+  list->caps = 0;
+  return;
+}

src/filelist.h

@@ -0,0 +1,57 @@
+#ifndef FILELIST_H_
+#define FILELIST_H_ 1
+
+/** Filelist of potential images */
+typedef struct {
+  int size; /**< files in list */
+  int caps; /**< allocated slots count */
+  char **files; /**< Path's array */
+} filelist_t;
+
+/**
+ * @brief Create new filelist
+ * @param size Preallocated list slots count
+ * @returns Pointer to created list or NULL on error
+ */
+filelist_t * filelist_create(int size);
+
+/**
+ * @brief Get image path by id
+ * @param list Pointer to filelist
+ * @param num  Image number
+ * @returns Pointer to image path or NULL if slot is empty
+ */
+const char * filelist_get (filelist_t *list, int num);
+
+/**
+ * @brief Add new path to filelist
+ * @param list Pointer to filelist
+ * @param path Path to image
+ * @returns 0 on error or >0 on success as slot number
+ */
+int filelist_append (filelist_t *list, const char *path);
+
+/**
+ * @brief Replace given slot with new path
+ * @param list Pointer to filelist
+ * @param num  Image number
+ * @param path Path to image
+ * @returns true on success, false on error
+ */
+bool filelist_set (filelist_t *list, int num, const char *path);
+
+/**
+ * @brief Remove path with given slot number
+ * @param list Pointer to filelist
+ * @param num  Image number
+ */
+void filelist_del (filelist_t *list, int num);
+
+/**
+ * @brief Remove all filelist members and free memory
+ * @param list Pointer to filelist
+ * @note memory for filelist_t struct not freed
+ */
+void filelist_free(filelist_t *list);
+
+#endif /* FILELIST_H_ */