advent2019

commit 399aed28d8e41cfef8b225fd082ac4897aece33d
parent e6a73e442a2aebf2e03a46d10a4652e9c9349a15
Author: bsandro <email@bsandro.tech>
Date:   Fri, 27 Feb 2026 01:22:15 +0200

array.h draft

Diffstat:
A
array.h
 | 
40
++++++++++++++++++++++++++++++++++++++++

1 file changed, 40 insertions(+), 0 deletions(-)
diff --git a/array.h b/array.h
@@ -0,0 +1,40 @@
+#include <stdlib.h>
+
+struct array_hdr {
+    size_t len;
+    size_t cap;
+};
+
+#define array_init(ar, capacity) do {                                                   \
+    struct array_hdr *hdr = malloc(sizeof(struct array_hdr)+sizeof(*(ar))*(capacity));  \
+    printf("init %p\n", (void *)hdr);                                                   \
+    hdr->len = 0;                                                                       \
+    hdr->cap = (capacity);                                                              \
+    (ar) = (void *)(hdr+1);                                                             \
+} while(0);
+
+#define array_free(ar) do {                     \
+    void *base = ((struct array_hdr *)(ar))-1;  \
+    printf("free %p\n", (void *)base);          \
+    free(base);                                 \
+    (ar) = NULL;                                \
+} while(0);
+
+inline size_t array_len(void *ar) {
+    return (((struct array_hdr *)ar)-1)->len;
+}
+
+inline size_t array_cap(void *ar) {
+    return (((struct array_hdr *)ar)-1)->cap;
+}
+
+#define array_push(ar, val) do {                                                \
+    struct array_hdr *hdr = ((struct array_hdr *)(ar))-1;                       \
+    printf("push: %lu of %lu\n", hdr->len, hdr->cap);                           \
+    if (hdr->len+1>=hdr->cap) {                                                 \
+        hdr = realloc(hdr, sizeof(*ar)*hdr->cap*2+sizeof(struct array_hdr));    \
+        hdr->cap*=2;                                                            \
+        (ar) = (void *)(hdr+1);                                                 \
+    }                                                                           \
+    (ar)[hdr->len++] = val;                                                     \
+} while(0);