From 745440b1e766c3ca5534f4ce7f6c4fec27a3b487 Mon Sep 17 00:00:00 2001
From: Pietro Gagliardi <pietro10@mac.com>
Date: Sun, 19 May 2019 12:52:06 -0400
Subject: [PATCH] Wrote array manipulation functions. Now to convert events.c
 to use them.

---
 common/alloc.c  | 65 +++++++++++++++++++++++++++++++++++++++++++++++++
 common/uipriv.h | 24 ++++++++++++++++++
 2 files changed, 89 insertions(+)

diff --git a/common/alloc.c b/common/alloc.c
index ce90c453..17106e46 100644
--- a/common/alloc.c
+++ b/common/alloc.c
@@ -29,3 +29,68 @@ void uiprivFree(void *p)
 {
 	free(p);
 }
+
+void *uiprivArrayAppend(uiprivArray *arr, size_t n)
+{
+	return uiprivArrayInsertAt(arr, arr->len, n);
+}
+
+void *uiprivArrayInsertAt(uiprivArray *arr, size_t pos, size_t n)
+{
+	uint8_t *old, *new;
+	size_t nBytes;
+
+	if ((arr->len + n) >= arr->cap) {
+		size_t nGrow;
+
+		// always grow by a perfect multiple of arr->nGrow
+		nGrow = n + (arr->nGrow - (n % arr->nGrow));
+		arr->buf = uiprivRealloc(arr->buf,
+			arr->cap * arr->elemsize,
+			(arr->cap + nGrow) * arr->elemsize,
+			arr->what);
+		arr->cap += nGrow;
+	}
+	arr->len += n;
+
+	nBytes = n * arr->elemsize;
+	new = ((uint8_t *) (arr->buf)) + (pos * arr->elemsize);
+	old = new + nBytes;
+	memmove(old, new, nBytes);
+	memset(new, 0, nBytes);
+	return new;
+}
+
+void uiprivArrayDelete(uiprivArray *arr, size_t pos, size_t n)
+{
+	uint8_t *src, *dest;
+	size_t nBytesDeleted, nBytesRemaining;
+
+	nBytesDeleted = n * arr->elemsize;
+	nBytesRemaining = (arr->len - pos - n) * arr->elemsize;
+	dest = ((uint8_t *) (arr->buf)) + (pos * arr->elemsize);
+	src = dest + nBytesDeleted;
+	memmove(dest, src, nBytesDeleted);
+	memset(src, 0, nBytesRemaining);
+	arr->len -= n;
+}
+
+void uiprivArrayDeleteItem(uiprivArray *arr, void *p, size_t n)
+{
+	uint8_t *p8, *buf8;
+
+	p8 = (uint8_t *) p;
+	buf8 = (uint8_t *) (arr->buf);
+	// TODO write this in a way that doesn't mix ptrdiff_t and size_t
+	uiprivArrayDelete(arr, (p8 - buf8) / arr->elemsize, n);
+}
+
+void *uiprivArrayBsearch(uiprivArray *arr, const void *key, int (*compare)(const void *, const void *))
+{
+	return bsearch(key, arr->buf, arr->len, arr->elemsize, compare);
+}
+
+void uiprivArrayQsort(uiprivArray *arr, int (*compare)(const void *, const void *))
+{
+	qsort(arr->buf, arr->len, arr->elemsize, compare);
+}
diff --git a/common/uipriv.h b/common/uipriv.h
index c4d8ef12..9ffdf57c 100644
--- a/common/uipriv.h
+++ b/common/uipriv.h
@@ -14,6 +14,30 @@ extern int uiprivInitReturnErrorf(uiInitError *err, const char *msg, ...);
 extern void *uiprivAlloc(size_t n, const char *what);
 extern void *uiprivRealloc(void *p, size_t old, size_t new, const char *what);
 extern void uiprivFree(void *p);
+typedef struct uiprivArray uiprivArray;
+struct uiprivArray {
+	void *buf;
+	size_t len;
+	size_t cap;
+	size_t elemsize;
+	size_t nGrow;
+	const char *what;
+};
+#define uiprivInitArray(arr, T, grow) \
+	memset(&arr, 0, sizeof (uiprivArray)); \
+	arr.elemsize = sizeof (T); \
+	arr.nGrow = grow; \
+	arr.what = #T "[]";
+#define uiprivFreeArray(arr) \
+	uiprivFree(arr.buf); \
+	memset(&arr, 0, sizeof (uiprivArray);
+#define uiprivArrayAt(arr, T, n) (((T *) (arr.buf)) + (n))
+extern void *uiprivArrayAppend(uiprivArray *arr, size_t n);
+extern void *uiprivArrayInsertAt(uiprivArray *arr, size_t pos, size_t n);
+extern void uiprivArrayDelete(uiprivArray *arr, size_t pos, size_t n);
+extern void uiprivArrayDeleteItem(uiprivArray *arr, void *p, size_t n);
+extern void *uiprivArrayBsearch(uiprivArray *arr, const void *key, int (*compare)(const void *, const void *));
+extern void uiprivArrayQsort(uiprivArray *arr, int (*compare)(const void *, const void *));
 
 // errors.c
 extern void uiprivInternalError(const char *fmt, ...);