From 5534e07c2428109ccd5bc47fbc197ae8b78d83f6 Mon Sep 17 00:00:00 2001
From: "yu.dongliang" <18588496441@163.com>
Date: Mon, 27 Nov 2023 12:00:54 +0800
Subject: [PATCH] a simple 'malloc()' example: ../test/scf_malloc.c
---
test/m1.c | 260 ----------------------------------------
test/m2.c | 33 ------
test/malloc_free.c | 288 ---------------------------------------------
test/scf_malloc.c | 28 +++++
4 files changed, 28 insertions(+), 581 deletions(-)
delete mode 100644 test/m1.c
delete mode 100644 test/m2.c
delete mode 100644 test/malloc_free.c
diff --git a/test/m1.c b/test/m1.c
deleted file mode 100644
index 87fb05e..0000000
--- a/test/m1.c
+++ /dev/null
@@ -1,260 +0,0 @@
-
-int scf__brk (uint8_t* addr);
-uint8_t* scf__sbrk(uintptr_t inc);
-
-int scf_printf(const char* fmt, ...);
-
-struct scf_mblock_t
-{
- uintptr_t prev;
- uintptr_t next;
- uintptr_t size;
-};
-
-scf_mblock_t* scf__mblocks[30];
-scf_mblock_t* scf__free_blocks = NULL;
-uint8_t* scf__last_brk = NULL;
-
-uint8_t* scf__malloc(uintptr_t size)
-{
- scf_mblock_t* b;
- scf_mblock_t* b2;
-
- uintptr_t bytes = (sizeof(scf_mblock_t) + size + 63) >> 6 << 6;
- intptr_t nblocks = sizeof(scf__mblocks) / sizeof(scf__mblocks[0]);
-
- uintptr_t rest;
- uint8_t* addr = NULL;
- uint8_t* p = NULL;
- intptr_t i;
-
- for (i = 0; i < nblocks; i++) {
-
- if ((64 << i) < bytes)
- continue;
-
- if (scf__mblocks[i])
- break;
- }
-
- if (i == nblocks) {
-
- uintptr_t pages = (bytes + 4095) >> 12;
-
- p = scf__sbrk(pages << 12);
- if (!p)
- return NULL;
- scf__last_brk = p + (pages << 12);
-
- rest = (pages << 12) - bytes;
-
- b = (scf_mblock_t*)p;
-
- b->prev = 0x3;
- b->next = bytes;
-
- } else {
- b = scf__mblocks[i];
- scf__mblocks[i] = (scf_mblock_t*)b->size;
-
- uintptr_t bytes2;
- if (b->prev & 0x2)
- bytes2 = b->next;
- else
- bytes2 = b->next - (uintptr_t)b;
-
- p = (uint8_t*)b;
-
- rest = bytes2 - bytes;
- }
-
- addr = p + sizeof(scf_mblock_t);
-
- if (0 == rest)
- return addr;
-
- p += bytes;
- b2 = (scf_mblock_t*)p;
-
- for (; i >= 0; i--) {
-
- if (rest >= (64 << i)) {
- b2->size = (uintptr_t)scf__mblocks[i];
- scf__mblocks[i] = b2;
- break;
- }
- }
-
- b ->next = (uintptr_t)b2;
- b2->prev = (uintptr_t)b;
-
- if (b->prev & 0x2) {
- b2->prev |= 0x2;
- b2->prev &= ~0x4;
- b ->prev &= ~0x2;
- b2->next = rest;
- }
-
- return addr;
-}
-
-int scf__free(uint8_t* p)
-{
- p -= sizeof(scf_mblock_t);
-
- scf_mblock_t* b = (scf_mblock_t*)p;
- scf_mblock_t* b2;
- scf_mblock_t* b3;
- scf_mblock_t** pb;
-
- uintptr_t bytes;
- if (b->prev & 0x2)
- bytes = b->next;
- else
- bytes = b->next - (uintptr_t)b;
-
- intptr_t nblocks = sizeof(scf__mblocks) / sizeof(scf__mblocks[0]);
- intptr_t i;
-
- for (i = nblocks - 1; i >= 0; i--) {
-
- if (bytes >= (64 << i))
- break;
- }
-
- while (!(b->prev & 0x2)) {
-
- b2 = (scf_mblock_t*)b->next;
-
- uintptr_t bytes2;
- if (b2->prev & 0x2)
- bytes2 = b2->next;
- else
- bytes2 = b2->next - (uintptr_t)b2;
-
- for (i = nblocks - 1; i >= 0; i--) {
-
- if (bytes2 >= (64 << i))
- break;
- }
-
- for (pb = &scf__mblocks[i]; *pb; pb = (scf_mblock_t**)&(*pb)->size) {
-
- if (*pb == b2)
- break;
- }
- if (!*pb)
- break;
-
- *pb = (scf_mblock_t*)b2->size;
-
- bytes += bytes2;
-
- if (b2->prev & 0x2) {
- b->prev |= 0x2;
- b->next = bytes;
- } else {
- b3 = (scf_mblock_t*)b2->next;
- b->next = b2->next;
- b3->prev = (uintptr_t)b | (b3->prev & 0x3);
- }
- }
-
- while (!(b->prev & 0x1)) {
-
- b2 = (scf_mblock_t*)(b->prev & ~0x7);
-
- uintptr_t bytes2 = (uintptr_t)b - (uintptr_t)b2;
-
- for (i = nblocks - 1; i >= 0; i--) {
-
- if (bytes2 >= (64 << i))
- break;
- }
-
- for (pb = &scf__mblocks[i]; *pb; pb = (scf_mblock_t**)&(*pb)->size) {
- if (*pb == b2)
- break;
- }
- if (!*pb)
- break;
-
- *pb = (scf_mblock_t*)b2->size;
-
- bytes += bytes2;
-
- if (b->prev & 0x2) {
- b2->prev |= 0x2;
- b2->next = bytes;
-
- } else {
- b3 = (scf_mblock_t*)b->next;
- b2->next = b->next;
- b3->prev = (uintptr_t)b2 | (b3->prev & 0x3);
- }
-
- b = b2;
- }
-
- if (b->prev & 0x2)
- bytes = b->next;
- else
- bytes = b->next - (uintptr_t)b;
-
- if (0x3 == (b->prev) & 0x3) {
-
- if (scf__last_brk == (uint8_t*)b + bytes) {
-
- scf__last_brk = (uint8_t*)b;
- scf__brk((uint8_t*)b);
-
- int flag = 1;
- while (flag) {
- flag = 0;
-
- pb = &scf__free_blocks;
- while (*pb) {
-
- b = *pb;
- bytes = b->next;
-
- if (scf__last_brk != (uint8_t*)b + bytes) {
-
- pb = (scf_mblock_t**)&b->size;
- continue;
- }
- *pb = (scf_mblock_t*)b->size;
-
- scf__last_brk = (uint8_t*)b;
- scf__brk((uint8_t*)b);
- flag = 1;
- }
- }
- } else {
- b->size = (uintptr_t)scf__free_blocks;
- scf__free_blocks = b;
- }
- return 0;
- }
-
- for (i = nblocks - 1; i >= 0; i--) {
- if (bytes >= (64 << i))
- break;
- }
-
- b->size = (uintptr_t)scf__mblocks[i];
- scf__mblocks[i] = b;
-
- return 0;
-}
-
-int main()
-{
- uint8_t* p0 = scf__malloc(1000);
- uint8_t* p1 = scf__malloc(1320);
-
- scf__free(p0);
- scf__free(p1);
- return 0;
-}
-
diff --git a/test/m2.c b/test/m2.c
deleted file mode 100644
index 5e6de66..0000000
--- a/test/m2.c
+++ /dev/null
@@ -1,33 +0,0 @@
-
-uint8_t* scf__malloc(uintptr_t size);
-int scf__free(uint8_t* p);
-
-int main()
-{
- uint8_t* p0 = scf__malloc(1000);
- uint8_t* p1 = scf__malloc(1320);
- uint8_t* p2 = scf__malloc(2510);
- uint8_t* p3 = scf__malloc(4510);
- uint8_t* p4 = scf__malloc(510);
- uint8_t* p5 = scf__malloc(6510);
- uint8_t* p6 = scf__malloc(510);
- uint8_t* p7 = scf__malloc(11510);
-
- scf__free(p0);
-
- *p1 = 1;
- scf__free(p1);
-
- *p2 = 2;
- *p4 = 4;
-
- scf__free(p4);
- scf__free(p5);
- scf__free(p2);
- scf__free(p6);
- scf__free(p3);
-
- scf__free(p7);
- return 0;
-}
-
diff --git a/test/malloc_free.c b/test/malloc_free.c
deleted file mode 100644
index 508fd45..0000000
--- a/test/malloc_free.c
+++ /dev/null
@@ -1,288 +0,0 @@
-
-int scf__brk (uint8_t* addr);
-uint8_t* scf__sbrk(uintptr_t inc);
-
-int scf_printf(const char* fmt, ...);
-
-struct scf_mblock_t
-{
- uintptr_t prev;
- uintptr_t next;
- uintptr_t size;
-};
-
-scf_mblock_t* scf__mblocks[30];
-scf_mblock_t* scf__free_blocks = NULL;
-uint8_t* scf__last_brk = NULL;
-
-uint8_t* scf__malloc(uintptr_t size)
-{
- scf_mblock_t* b;
- scf_mblock_t* b2;
-
- uintptr_t bytes = (sizeof(scf_mblock_t) + size + 63) >> 6 << 6;
- intptr_t nblocks = sizeof(scf__mblocks) / sizeof(scf__mblocks[0]);
-
- uintptr_t rest;
- uint8_t* addr = NULL;
- uint8_t* p = NULL;
- intptr_t i;
-
- for (i = 0; i < nblocks; i++) {
-
- if ((64 << i) < bytes)
- continue;
-
- if (scf__mblocks[i])
- break;
- }
-
- if (i == nblocks) {
-
- uintptr_t pages = (bytes + 4095) >> 12;
-
- p = scf__sbrk(pages << 12);
- if (!p)
- return NULL;
- scf__last_brk = p + (pages << 12);
-
- rest = (pages << 12) - bytes;
-
- b = (scf_mblock_t*)p;
-
- b->prev = 0x3;
- b->next = bytes;
-
- } else {
- b = scf__mblocks[i];
- scf__mblocks[i] = (scf_mblock_t*)b->size;
-
- uintptr_t bytes2;
- if (b->prev & 0x2)
- bytes2 = b->next;
- else
- bytes2 = b->next - (uintptr_t)b;
-
- p = (uint8_t*)b;
-
- rest = bytes2 - bytes;
- }
-
- addr = p + sizeof(scf_mblock_t);
-
- if (0 == rest) {
- scf_printf("74, b: %p, scf__last_brk: %#lx\n", b, scf__last_brk);
- return addr;
- }
-
- p += bytes;
- b2 = (scf_mblock_t*)p;
-
- for (; i >= 0; i--) {
-
- if (rest >= (64 << i)) {
- b2->size = (uintptr_t)scf__mblocks[i];
- scf__mblocks[i] = b2;
- break;
- }
- }
-
- b ->next = (uintptr_t)b2;
- b2->prev = (uintptr_t)b;
-
- if (b->prev & 0x2) {
- b2->prev |= 0x2;
- b2->prev &= ~0x4;
- b ->prev &= ~0x2;
- b2->next = rest;
- }
-
- scf_printf("100, b: %p, scf__last_brk: %#lx\n", b, scf__last_brk);
- return addr;
-}
-
-int scf__free(uint8_t* p)
-{
- p -= sizeof(scf_mblock_t);
-
- scf_mblock_t* b = (scf_mblock_t*)p;
- scf_mblock_t* b2;
- scf_mblock_t* b3;
- scf_mblock_t** pb;
-
- uintptr_t bytes;
- if (b->prev & 0x2)
- bytes = b->next;
- else
- bytes = b->next - (uintptr_t)b;
-
- intptr_t nblocks = sizeof(scf__mblocks) / sizeof(scf__mblocks[0]);
- intptr_t i;
-
- for (i = nblocks - 1; i >= 0; i--) {
-
- if (bytes >= (64 << i))
- break;
- }
-
- while (!(b->prev & 0x2)) {
-
- b2 = (scf_mblock_t*)b->next;
-
- uintptr_t bytes2;
- if (b2->prev & 0x2)
- bytes2 = b2->next;
- else
- bytes2 = b2->next - (uintptr_t)b2;
-
- for (i = nblocks - 1; i >= 0; i--) {
-
- if (bytes2 >= (64 << i))
- break;
- }
-
- for (pb = &scf__mblocks[i]; *pb; pb = (scf_mblock_t**)&(*pb)->size) {
-
- if (*pb == b2)
- break;
- }
- if (!*pb)
- break;
-
- *pb = (scf_mblock_t*)b2->size;
-
- bytes += bytes2;
-
- if (b2->prev & 0x2) {
- b->prev |= 0x2;
- b->next = bytes;
- } else {
- b3 = (scf_mblock_t*)b2->next;
- b->next = b2->next;
- b3->prev = (uintptr_t)b | (b3->prev & 0x3);
- }
- }
-
- while (!(b->prev & 0x1)) {
-
- b2 = (scf_mblock_t*)(b->prev & ~0x7);
-
- uintptr_t bytes2 = (uintptr_t)b - (uintptr_t)b2;
-
- for (i = nblocks - 1; i >= 0; i--) {
-
- if (bytes2 >= (64 << i))
- break;
- }
-
- for (pb = &scf__mblocks[i]; *pb; pb = (scf_mblock_t**)&(*pb)->size) {
- if (*pb == b2)
- break;
- }
- if (!*pb)
- break;
-
- *pb = (scf_mblock_t*)b2->size;
-
- bytes += bytes2;
-
- if (b->prev & 0x2) {
- b2->prev |= 0x2;
- b2->next = bytes;
-
- } else {
- b3 = (scf_mblock_t*)b->next;
- b2->next = b->next;
- b3->prev = (uintptr_t)b2 | (b3->prev & 0x3);
- }
-
- b = b2;
- }
-
- if (b->prev & 0x2)
- bytes = b->next;
- else
- bytes = b->next - (uintptr_t)b;
-
- if (0x3 == (b->prev) & 0x3) {
-
- if (scf__last_brk == (uint8_t*)b + bytes) {
-
- scf_printf("211, b: %p, scf__last_brk: %#lx\n", b, scf__last_brk);
-
- scf__last_brk = (uint8_t*)b;
- scf__brk((uint8_t*)b);
-
- int flag = 1;
- while (flag) {
- flag = 0;
-
- pb = &scf__free_blocks;
- while (*pb) {
-
- b = *pb;
- bytes = b->next;
-
- if (scf__last_brk != (uint8_t*)b + bytes) {
-
- pb = (scf_mblock_t**)&b->size;
- continue;
- }
- *pb = (scf_mblock_t*)b->size;
-
- scf_printf("232, b: %p, scf__last_brk: %#lx\n", b, scf__last_brk);
-
- scf__last_brk = (uint8_t*)b;
- scf__brk((uint8_t*)b);
- flag = 1;
- }
- }
- } else {
- b->size = (uintptr_t)scf__free_blocks;
- scf__free_blocks = b;
- scf_printf("242, b: %p, scf__last_brk: %#lx\n", b, scf__last_brk);
- }
- return 0;
- }
-
- for (i = nblocks - 1; i >= 0; i--) {
- if (bytes >= (64 << i))
- break;
- }
-
- b->size = (uintptr_t)scf__mblocks[i];
- scf__mblocks[i] = b;
-
- scf_printf("255, b: %p\n", b);
- return 0;
-}
-
-int main()
-{
- uint8_t* p0 = scf__malloc(1000);
- uint8_t* p1 = scf__malloc(1320);
- uint8_t* p2 = scf__malloc(2510);
- uint8_t* p3 = scf__malloc(4510);
- uint8_t* p4 = scf__malloc(510);
- uint8_t* p5 = scf__malloc(6510);
- uint8_t* p6 = scf__malloc(510);
- uint8_t* p7 = scf__malloc(11510);
-
- scf__free(p0);
-
- *p1 = 1;
- scf__free(p1);
-
- *p2 = 2;
- *p4 = 4;
-
- scf__free(p4);
- scf__free(p5);
- scf__free(p2);
- scf__free(p6);
- scf__free(p3);
-
- scf__free(p7);
- return 0;
-}
-
diff --git a/test/scf_malloc.c b/test/scf_malloc.c
index 3807802..bf204b0 100644
--- a/test/scf_malloc.c
+++ b/test/scf_malloc.c
@@ -334,3 +334,31 @@ uint8_t* scf__realloc(uint8_t* p, uintptr_t size)
return p;
}
+int main()
+{
+ uint8_t* p0 = scf__malloc(1000);
+ uint8_t* p1 = scf__malloc(1320);
+ uint8_t* p2 = scf__malloc(2510);
+ uint8_t* p3 = scf__malloc(4510);
+ uint8_t* p4 = scf__malloc(510);
+ uint8_t* p5 = scf__malloc(6510);
+ uint8_t* p6 = scf__malloc(510);
+ uint8_t* p7 = scf__malloc(11510);
+
+ scf__free(p0);
+
+ *p1 = 1;
+ scf__free(p1);
+
+ *p2 = 2;
+ *p4 = 4;
+
+ scf__free(p4);
+ scf__free(p5);
+ scf__free(p2);
+ scf__free(p6);
+ scf__free(p3);
+
+ scf__free(p7);
+ return 0;
+}
--
2.25.1