1 files changed, 55 insertions, 0 deletions
diff --git a/include/common.h b/include/common.h
new file mode 100644
index 0000000..6fd9820
--- /dev/null
+++ b/include/common.h
@@ -0,0 +1,55 @@
+#ifndef ECEX_COMMON_H
+#define ECEX_COMMON_H
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ECEX_OK 0
+#define ECEX_ERR (-1)
+
+#define ECEX_ARRAY_LEN(a) (sizeof(a) / sizeof((a)[0]))
+#define ECEX_MIN(a, b) ((a) < (b) ? (a) : (b))
+#define ECEX_MAX(a, b) ((a) > (b) ? (a) : (b))
+#define ECEX_CLAMP(v, lo, hi) (ECEX_MAX((lo), ECEX_MIN((v), (hi))))
+
+#define ECEX_RETURN_ERR_IF_NULL(p) \
+    do { \
+        if (!(p)) return ECEX_ERR; \
+    } while (0)
+
+#define ECEX_RETURN_NULL_IF_NULL(p) \
+    do { \
+        if (!(p)) return NULL; \
+    } while (0)
+
+#define ECEX_FREE_AND_NULL(p) \
+    do { \
+        free(p); \
+        (p) = NULL; \
+    } while (0)
+
+#define ECEX_GROW_ARRAY(ptr, count, cap, initial_cap) \
+    ecex_grow_array((void **)&(ptr), sizeof(*(ptr)), (count), &(cap), (initial_cap))
+
+static inline int ecex_grow_array(void **ptr,
+                                  size_t item_size,
+                                  size_t count,
+                                  size_t *cap,
+                                  size_t initial_cap) {
+    if (count < *cap) return ECEX_OK;
+
+    size_t new_cap = *cap ? *cap * 2 : initial_cap;
+    while (new_cap <= count) {
+        new_cap *= 2;
+    }
+
+    void *new_ptr = realloc(*ptr, new_cap * item_size);
+    if (!new_ptr) return ECEX_ERR;
+
+    *ptr = new_ptr;
+    *cap = new_cap;
+    return ECEX_OK;
+}
+
+#endif