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将Nginx源码数组结构(ngx_array.c)和内存池代码单独编译运行，附代码

news 2025/7/7 6:48:53

在上面一篇的基础上把Nginx源码数组结构也摘录下来，也增加了测试代码，编译运行。
https://blog.csdn.net/katerdaisy/article/details/132358883
《将nginx内存池代码单独编译运行，了解nginx内存池工作原理，附代码》

在这里插入图片描述

核心代码：

//在内存数组中分三次写入 "hello", "world", "!",然后使用指针加偏移，地址加数据长度两种方式将保存在数组中的文字打印出来
// char mychar[6] = "hello";
// ngx_str_t mydata = {sizeof(mychar),mychar};
ngx_array_t *a = NULL;
a = ngx_array_create(pool, 1, sizeof(ngx_str_t));ngx_str_t *s = ngx_array_push(a);
s->data = "hello";
s->len = sizeof(s->data);
printf("a->nelts: %ld, a->nalloc:%ld\n",a->nelts,a->nalloc);
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts))->data);
printf("ngx_array_push:%s\n",s->data);ngx_str_t *s1 = ngx_array_push(a);
s1->data = "wrold";
s1->len = sizeof(s1->data);
printf("a->nelts: %ld, a->nalloc:%ld\n",a->nelts,a->nalloc);
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts+sizeof(ngx_str_t)))->data);//地址加数据长度
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts)+1)->data); //使用指针加偏移
printf("ngx_array_push:%s\n",s1->data);ngx_str_t *s2 = ngx_array_push(a);
s2->data = "!";
s2->len = sizeof(s2->data);
printf("a->nelts: %ld, a->nalloc:%ld\n",a->nelts,a->nalloc);
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts+sizeof(ngx_str_t)*(a->nelts-1)))->data);//地址加数据长度
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts)+a->nelts-1)->data); //使用指针加偏移
printf("ngx_array_push:%s\n",s2->data);

结果：

在这里插入图片描述

完整代码：

//-------------------------------------------------------------------------------------------
//下面是一些头文件和宏定义，从nginx的源码中摘录过来
#include </usr/include/stdint.h>
#include <sys/types.h>
#include <sys/time.h>
#include <unistd.h>
#include <stdarg.h>
#include <stddef.h> /* offsetof() /
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <signal.h>
#include <pwd.h>
#include <grp.h>
#include <dirent.h>
#include <glob.h>
#include <sys/vfs.h> / statfs() */

#include <sys/uio.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <sys/wait.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <sched.h>

#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h> /* TCP_NODELAY, TCP_CORK */
#include <arpa/inet.h>
#include <netdb.h>
#include <sys/un.h>

#include <time.h> /* tzset() /
#include <malloc.h> / memalign() /
#include <limits.h> / IOV_MAX /
#include <sys/ioctl.h>
#include <crypt.h>
#include <sys/utsname.h> / uname() */

#include <dlfcn.h>

#ifndef ngx_inline
#define ngx_inline inline
#endif

typedef int ngx_fd_t;
typedef intptr_t ngx_int_t;
typedef uintptr_t ngx_uint_t;
typedef intptr_t ngx_flag_t;
typedef struct ngx_module_s ngx_module_t;
typedef struct ngx_conf_s ngx_conf_t;
typedef struct ngx_cycle_s ngx_cycle_t;
typedef struct ngx_pool_s ngx_pool_t;
typedef struct ngx_chain_s ngx_chain_t;
typedef struct ngx_log_s ngx_log_t;
typedef struct ngx_open_file_s ngx_open_file_t;
typedef struct ngx_command_s ngx_command_t;
typedef struct ngx_file_s ngx_file_t;
typedef struct ngx_event_s ngx_event_t;
typedef struct ngx_event_aio_s ngx_event_aio_t;
typedef struct ngx_connection_s ngx_connection_t;

ngx_uint_t ngx_pagesize;
ngx_uint_t ngx_pagesize_shift;
ngx_uint_t ngx_cacheline_size;

// #define NGX_LOG_STDERR 0
// #define NGX_LOG_EMERG 1
// #define NGX_LOG_ALERT 2
// #define NGX_LOG_CRIT 3
// #define NGX_LOG_ERR 4
// #define NGX_LOG_WARN 5
// #define NGX_LOG_NOTICE 6
// #define NGX_LOG_INFO 7
// #define NGX_LOG_DEBUG 8

// #define NGX_LOG_DEBUG_CORE 0x010
// #define NGX_LOG_DEBUG_ALLOC 0x020
// #define NGX_LOG_DEBUG_MUTEX 0x040
// #define NGX_LOG_DEBUG_EVENT 0x080
// #define NGX_LOG_DEBUG_HTTP 0x100
// #define NGX_LOG_DEBUG_MAIL 0x200
// #define NGX_LOG_DEBUG_STREAM 0x400

/*

  • do not forget to update debug_levels[] in src/core/ngx_log.c
  • after the adding a new debug level
    */

#define NGX_LOG_DEBUG_FIRST NGX_LOG_DEBUG_CORE
#define NGX_LOG_DEBUG_LAST NGX_LOG_DEBUG_STREAM
#define NGX_LOG_DEBUG_CONNECTION 0x80000000
#define NGX_LOG_DEBUG_ALL 0x7ffffff0

#ifndef NGX_PALLOC_H_INCLUDED
#define NGX_PALLOC_H_INCLUDED

#ifndef NGX_ALIGNMENT
#define NGX_ALIGNMENT sizeof(unsigned long) /* platform word */
#endif

#define NGX_OK 0
#define NGX_ERROR -1
#define NGX_AGAIN -2
#define NGX_BUSY -3
#define NGX_DONE -4
#define NGX_DECLINED -5
#define NGX_ABORT -6
#define NGX_INVALID_FILE -1
#define NGX_FILE_ERROR -1

#define ngx_errno errno
#define ngx_close_file close
#define ngx_close_file_n “close()”
typedef int ngx_err_t;
#define NGX_ENOENT ENOENT
#define ngx_delete_file_n “unlink()”

/*

  • NGX_MAX_ALLOC_FROM_POOL should be (ngx_pagesize - 1), i.e. 4095 on x86.
  • On Windows NT it decreases a number of locked pages in a kernel.
    */
    #define NGX_MAX_ALLOC_FROM_POOL (ngx_pagesize - 1)

#define NGX_DEFAULT_POOL_SIZE (16 * 1024)

#define NGX_POOL_ALIGNMENT 16
#define NGX_MIN_POOL_SIZE
ngx_align((sizeof(ngx_pool_t) + 2 * sizeof(ngx_pool_large_t)),
NGX_POOL_ALIGNMENT)

typedef void (*ngx_pool_cleanup_pt)(void *data);

typedef struct ngx_pool_cleanup_s ngx_pool_cleanup_t;

struct ngx_pool_cleanup_s {
ngx_pool_cleanup_pt handler;
void *data;
ngx_pool_cleanup_t *next;
};

typedef struct ngx_pool_large_s ngx_pool_large_t;

struct ngx_pool_large_s {
ngx_pool_large_t *next;
void *alloc;
};

typedef struct {
u_char *last;
u_char *end;
ngx_pool_t *next;
ngx_uint_t failed;
} ngx_pool_data_t;

struct ngx_pool_s {
ngx_pool_data_t d;
size_t max;
ngx_pool_t *current;
ngx_chain_t *chain;
ngx_pool_large_t *large;
ngx_pool_cleanup_t *cleanup;
ngx_log_t *log;
};

typedef struct {
ngx_fd_t fd;
u_char *name;
ngx_log_t *log;
} ngx_pool_cleanup_file_t;

void *ngx_alloc(size_t size, ngx_log_t *log);
void *ngx_calloc(size_t size, ngx_log_t *log);

ngx_pool_t *ngx_create_pool(size_t size, ngx_log_t *log);
void ngx_destroy_pool(ngx_pool_t *pool);
void ngx_reset_pool(ngx_pool_t *pool);

void *ngx_palloc(ngx_pool_t *pool, size_t size);
void *ngx_pnalloc(ngx_pool_t *pool, size_t size);
void *ngx_pcalloc(ngx_pool_t *pool, size_t size);
void *ngx_pmemalign(ngx_pool_t *pool, size_t size, size_t alignment);
ngx_int_t ngx_pfree(ngx_pool_t *pool, void *p);

ngx_pool_cleanup_t *ngx_pool_cleanup_add(ngx_pool_t *p, size_t size);
void ngx_pool_run_cleanup_file(ngx_pool_t *p, ngx_fd_t fd);
void ngx_pool_cleanup_file(void *data);
void ngx_pool_delete_file(void *data);

#endif /* NGX_PALLOC_H_INCLUDED */

ngx_uint_t ngx_pagesize;
ngx_uint_t ngx_pagesize_shift;
ngx_uint_t ngx_cacheline_size;
#define ngx_free free
#define ngx_memzero(buf, n) (void) memset(buf, 0, n)
#define ngx_memset(buf, c, n) (void) memset(buf, c, n)
#define ngx_align_ptr(p, a)
(u_char *) (((uintptr_t) § + ((uintptr_t) a - 1)) & ~((uintptr_t) a - 1))
#define ngx_delete_file(name) unlink((const char *) name)
#define ngx_delete_file_n “unlink()”

void *
ngx_alloc(size_t size, ngx_log_t *log)
{
void *p;

p = malloc(size);
if (p == NULL) {printf("malloc(%lu) failed\n", size);
}printf("malloc: %p:%lu\n", p, size);return p;

}

void *
ngx_calloc(size_t size, ngx_log_t *log)
{
void *p;

p = ngx_alloc(size, log);if (p) {ngx_memzero(p, size);
}return p;

}

//#define NGX_HAVE_POSIX_MEMALIGN 1
#define NGX_HAVE_MEMALIGN 1
#if (NGX_HAVE_POSIX_MEMALIGN)

void *
ngx_memalign(size_t alignment, size_t size, ngx_log_t *log)
{
void *p;
int err;

err = posix_memalign(&p, alignment, size);if (err) {printf("posix_memalign(%lu, %lu) failed\n", alignment, size);p = NULL;
}printf("posix_memalign: %p:%lu @%lu\n", p, size, alignment);return p;

}

#elif (NGX_HAVE_MEMALIGN)

void *
ngx_memalign(size_t alignment, size_t size, ngx_log_t *log)
{
void *p;

p = memalign(alignment, size);
if (p == NULL) {printf("memalign(%lu, %lu) failed\n", alignment, size);
}printf("memalign: %p:%lu @%lu\n", p, size, alignment);return p;

}

#endif

//-------------------------------------------------------------------------------------------
//下面是从ngx_pcallo.c复制过来的内存池核心代码

static ngx_inline void *ngx_palloc_small(ngx_pool_t *pool, size_t size,
ngx_uint_t align);
static void *ngx_palloc_block(ngx_pool_t *pool, size_t size);
static void *ngx_palloc_large(ngx_pool_t *pool, size_t size);

ngx_pool_t *
ngx_create_pool(size_t size, ngx_log_t *log)
{
ngx_pool_t *p;

p = ngx_memalign(NGX_POOL_ALIGNMENT, size, log);
if (p == NULL) {return NULL;
}p->d.last = (u_char *) p + sizeof(ngx_pool_t);
p->d.end = (u_char *) p + size;
p->d.next = NULL;
p->d.failed = 0;size = size - sizeof(ngx_pool_t);
p->max = (size < NGX_MAX_ALLOC_FROM_POOL) ? size : NGX_MAX_ALLOC_FROM_POOL;p->current = p;
p->chain = NULL;
p->large = NULL;
p->cleanup = NULL;
p->log = log;return p;

}

void
ngx_destroy_pool(ngx_pool_t *pool)
{
ngx_pool_t *p, *n;
ngx_pool_large_t *l;
ngx_pool_cleanup_t *c;

for (c = pool->cleanup; c; c = c->next) {if (c->handler) {printf("run cleanup: %p\n", c);c->handler(c->data);}
}

#if (NGX_DEBUG)

/** we could allocate the pool->log from this pool* so we cannot use this log while free()ing the pool*/for (l = pool->large; l; l = l->next) {printf("free: %p\n", l->alloc);
}for (p = pool, n = pool->d.next; /* void */; p = n, n = n->d.next) {printf("free: %p, unused: %lu\n", p, p->d.end - p->d.last);if (n == NULL) {break;}
}

#endif

for (l = pool->large; l; l = l->next) {if (l->alloc) {ngx_free(l->alloc);}
}for (p = pool, n = pool->d.next; /* void */; p = n, n = n->d.next) {ngx_free(p);if (n == NULL) {break;}
}

}

void
ngx_reset_pool(ngx_pool_t *pool)
{
ngx_pool_t *p;
ngx_pool_large_t *l;

for (l = pool->large; l; l = l->next) {if (l->alloc) {ngx_free(l->alloc);}
}for (p = pool; p; p = p->d.next) {p->d.last = (u_char *) p + sizeof(ngx_pool_t);p->d.failed = 0;
}pool->current = pool;
pool->chain = NULL;
pool->large = NULL;

}

void *
ngx_palloc(ngx_pool_t *pool, size_t size)
{
#if !(NGX_DEBUG_PALLOC)
if (size <= pool->max) {
return ngx_palloc_small(pool, size, 1);
}
#endif

return ngx_palloc_large(pool, size);

}

void *
ngx_pnalloc(ngx_pool_t *pool, size_t size)
{
#if !(NGX_DEBUG_PALLOC)
if (size <= pool->max) {
return ngx_palloc_small(pool, size, 0);
}
#endif

return ngx_palloc_large(pool, size);

}

static ngx_inline void *
ngx_palloc_small(ngx_pool_t *pool, size_t size, ngx_uint_t align)
{
u_char *m;
ngx_pool_t *p;

p = pool->current;do {m = p->d.last;if (align) {m = ngx_align_ptr(m, NGX_ALIGNMENT);}if ((size_t) (p->d.end - m) >= size) {p->d.last = m + size;return m;}p = p->d.next;} while (p);return ngx_palloc_block(pool, size);

}

static void *
ngx_palloc_block(ngx_pool_t *pool, size_t size)
{
u_char *m;
size_t psize;
ngx_pool_t *p, *new;

psize = (size_t) (pool->d.end - (u_char *) pool);m = ngx_memalign(NGX_POOL_ALIGNMENT, psize, pool->log);
if (m == NULL) {return NULL;
}new = (ngx_pool_t *) m;new->d.end = m + psize;
new->d.next = NULL;
new->d.failed = 0;m += sizeof(ngx_pool_data_t);
m = ngx_align_ptr(m, NGX_ALIGNMENT);
new->d.last = m + size;for (p = pool->current; p->d.next; p = p->d.next) {if (p->d.failed++ > 4) {pool->current = p->d.next;}
}p->d.next = new;return m;

}

static void *
ngx_palloc_large(ngx_pool_t *pool, size_t size)
{
void *p;
ngx_uint_t n;
ngx_pool_large_t *large;

p = ngx_alloc(size, pool->log);
if (p == NULL) {return NULL;
}n = 0;for (large = pool->large; large; large = large->next) {if (large->alloc == NULL) {large->alloc = p;return p;}if (n++ > 3) {break;}
}large = ngx_palloc_small(pool, sizeof(ngx_pool_large_t), 1);
if (large == NULL) {ngx_free(p);return NULL;
}large->alloc = p;
large->next = pool->large;
pool->large = large;return p;

}

void *
ngx_pmemalign(ngx_pool_t *pool, size_t size, size_t alignment)
{
void *p;
ngx_pool_large_t *large;

p = ngx_memalign(alignment, size, pool->log);
if (p == NULL) {return NULL;
}large = ngx_palloc_small(pool, sizeof(ngx_pool_large_t), 1);
if (large == NULL) {ngx_free(p);return NULL;
}large->alloc = p;
large->next = pool->large;
pool->large = large;return p;

}

ngx_int_t
ngx_pfree(ngx_pool_t *pool, void *p)
{
ngx_pool_large_t *l;

for (l = pool->large; l; l = l->next) {if (p == l->alloc) {printf("free: %p\n", l->alloc);ngx_free(l->alloc);l->alloc = NULL;return NGX_OK;}
}return NGX_DECLINED;

}

void *
ngx_pcalloc(ngx_pool_t *pool, size_t size)
{
void *p;

p = ngx_palloc(pool, size);
if (p) {ngx_memzero(p, size);
}return p;

}

ngx_pool_cleanup_t *
ngx_pool_cleanup_add(ngx_pool_t *p, size_t size)
{
ngx_pool_cleanup_t *c;

c = ngx_palloc(p, sizeof(ngx_pool_cleanup_t));
if (c == NULL) {return NULL;
}if (size) {c->data = ngx_palloc(p, size);if (c->data == NULL) {return NULL;}} else {c->data = NULL;
}c->handler = NULL;
c->next = p->cleanup;p->cleanup = c;printf("add cleanup: %p\n", c);return c;

}

void
ngx_pool_run_cleanup_file(ngx_pool_t *p, ngx_fd_t fd)
{
ngx_pool_cleanup_t *c;
ngx_pool_cleanup_file_t *cf;

for (c = p->cleanup; c; c = c->next) {if (c->handler == ngx_pool_cleanup_file) {cf = c->data;if (cf->fd == fd) {c->handler(cf);c->handler = NULL;return;}}
}

}

void
ngx_pool_cleanup_file(void *data)
{
ngx_pool_cleanup_file_t *c = data;

printf("file cleanup: fd:%d\n",c->fd);if (ngx_close_file(c->fd) == NGX_FILE_ERROR) {printf(" \"%s\" failed\n", c->name);
}

}

void
ngx_pool_delete_file(void *data)
{
ngx_pool_cleanup_file_t *c = data;

ngx_err_t  err;printf("file cleanup: fd:%d %s\n",c->fd, c->name);if (ngx_delete_file(c->name) == NGX_FILE_ERROR) {err = ngx_errno;if (err != NGX_ENOENT) {printf(" \"%s\" failed\n", c->name);}
}if (ngx_close_file(c->fd) == NGX_FILE_ERROR) {printf(" \"%s\" failed\n", c->name);
}

}

#if 0

static void *
ngx_get_cached_block(size_t size)
{
void *p;
ngx_cached_block_slot_t *slot;

if (ngx_cycle->cache == NULL) {return NULL;
}slot = &ngx_cycle->cache[(size + ngx_pagesize - 1) / ngx_pagesize];slot->tries++;if (slot->number) {p = slot->block;slot->block = slot->block->next;slot->number--;return p;
}return NULL;

}

#endif
//-----------------------------------------------------------------------------------------
//array
typedef struct {
size_t len;
u_char *data;
} ngx_str_t;

#define ngx_memcpy(dst, src, n) (void) memcpy(dst, src, n)

#ifndef NGX_ARRAY_H_INCLUDED
#define NGX_ARRAY_H_INCLUDED

typedef struct {
void *elts;
ngx_uint_t nelts;
size_t size;
ngx_uint_t nalloc;
ngx_pool_t *pool;
} ngx_array_t;

ngx_array_t *ngx_array_create(ngx_pool_t *p, ngx_uint_t n, size_t size);
void ngx_array_destroy(ngx_array_t *a);
void *ngx_array_push(ngx_array_t *a);
void *ngx_array_push_n(ngx_array_t *a, ngx_uint_t n);

static ngx_inline ngx_int_t
ngx_array_init(ngx_array_t *array, ngx_pool_t pool, ngx_uint_t n, size_t size)
{
/
* set “array->nelts” before “array->elts”, otherwise MSVC thinks
* that “array->nelts” may be used without having been initialized
*/

array->nelts = 0;
array->size = size;
array->nalloc = n;
array->pool = pool;array->elts = ngx_palloc(pool, n * size);
if (array->elts == NULL) {return NGX_ERROR;
}return NGX_OK;

}

#endif /* NGX_ARRAY_H_INCLUDED */

ngx_array_t *
ngx_array_create(ngx_pool_t *p, ngx_uint_t n, size_t size)
{
ngx_array_t *a;

a = ngx_palloc(p, sizeof(ngx_array_t));
if (a == NULL) {return NULL;
}if (ngx_array_init(a, p, n, size) != NGX_OK) {return NULL;
}return a;

}

void
ngx_array_destroy(ngx_array_t *a)
{
ngx_pool_t *p;

p = a->pool;if ((u_char *) a->elts + a->size * a->nalloc == p->d.last) {p->d.last -= a->size * a->nalloc;
}if ((u_char *) a + sizeof(ngx_array_t) == p->d.last) {p->d.last = (u_char *) a;
}

}

void *
ngx_array_push(ngx_array_t *a)
{
void *elt, *new;
size_t size;
ngx_pool_t *p;

if (a->nelts == a->nalloc) {/* the array is full */size = a->size * a->nalloc;p = a->pool;if ((u_char *) a->elts + size == p->d.last&& p->d.last + a->size <= p->d.end){/** the array allocation is the last in the pool* and there is space for new allocation*/p->d.last += a->size;a->nalloc++;} else {/* allocate a new array */new = ngx_palloc(p, 2 * size);if (new == NULL) {return NULL;}ngx_memcpy(new, a->elts, size);a->elts = new;a->nalloc *= 2;}
}elt = (u_char *) a->elts + a->size * a->nelts;
a->nelts++;return elt;

}

void *
ngx_array_push_n(ngx_array_t *a, ngx_uint_t n)
{
void *elt, *new;
size_t size;
ngx_uint_t nalloc;
ngx_pool_t *p;

size = n * a->size;if (a->nelts + n > a->nalloc) {/* the array is full */p = a->pool;if ((u_char *) a->elts + a->size * a->nalloc == p->d.last&& p->d.last + size <= p->d.end){/** the array allocation is the last in the pool* and there is space for new allocation*/p->d.last += size;a->nalloc += n;} else {/* allocate a new array */nalloc = 2 * ((n >= a->nalloc) ? n : a->nalloc);new = ngx_palloc(p, nalloc * a->size);if (new == NULL) {return NULL;}ngx_memcpy(new, a->elts, a->nelts * a->size);a->elts = new;a->nalloc = nalloc;}
}elt = (u_char *) a->elts + a->size * a->nelts;
a->nelts += n;return elt;

}

//-------------------------------------------------------------------------------------------
//下面是Main函数和内存池打印代码

void print_pool(ngx_pool_t *pool)

{

if (pool->large != NULL){printf("has large memory\n");for(ngx_pool_large_t* i = pool->large; i!=NULL; i = i->next){printf("\t\tlarge next=0x%x\n", i->next);printf("\t\tlarge alloc=0x%x\n", i->alloc);}}int i=1;while(pool){printf("pool=0x%x,index:%d\n", pool, i++);printf("\t\tlast=0x%x\n", (pool->d).last);printf("\t\tend=0x%x\n",(pool->d).end);printf("\t\tnext=0x%x\n",(pool->d).next);printf("\t\tfailed=%d\n",pool->d.failed);printf("\t\tmax=%d\n",pool->max);printf("\t\tcurrent=0x%x\n",pool->current);printf("\t\tchain=0x%x\n",pool->chain);printf("\t\tlarge=0x%x\n",pool->large);printf("\t\tcleanup=0x%x\n",pool->cleanup);printf("\t\tlog=0x%x\n",pool->log);printf("\t\tavailable pool memory=%d\n", pool->d.end-pool->d.last);printf("\n");pool=pool->d.next;}}

void print_array(int *a,int size)

{

for(int i=0; i<size; i++){printf("%d,",a[i]);}printf("\n");

}

int main()

{

ngx_pool_t *pool;int array_size = 1;int array_size_large = 1024;int page_size = getpagesize();//获得一页的大小printf("page_size:%d\n", page_size);printf("----------------------------\n");printf("create a new pool\n");pool = ngx_create_pool(1024, NULL);//创建一个大小为1024的内存池print_pool(pool);printf("----------------------------\n");printf("alloc block 1 from the pool:\n");int *a1 = ngx_palloc(pool, sizeof(int) * array_size);//分配第一块内存 用于创建数组for (int i=0; i< array_size; i++){a1[i] = i+1;}print_pool(pool);printf("----------------------------\n");printf("alloc block 2 from the pool:\n");int *a2 = ngx_palloc(pool, sizeof(int) * array_size);//分配第二块内存 用于创建数组，这个时候会创建第二个内存池节点for (int i=0; i< array_size; i++){a2[i] = 12345678;}print_pool(pool);printf("----------------------------\n");printf("alloc large memory:\n");printf("\t\tlarge next before=0x%x\n", pool->current->d.last);int * a3 = ngx_palloc(pool, sizeof(int) * array_size_large);//由于大小超过了max的值 ngx_palloc中会调用ngx_palloc_large分配大块内存printf("\t\tlarge next after=0x%x\n", pool->large);for (int i=0; i< array_size_large; i++){a3[i] = i+1;}print_array(a1,array_size);//分配的第一块内存块首地址print_array(a2,array_size);//分配的第二块内存块首地址

// print_array(a3,array_size_large);//分配的大内存块首地址

//在内存数组中分三次写入 “hello”, “world”, “!”,然后使用指针加偏移，地址加数据长度两种方式将保存在数组中的文字打印出来
// char mychar[6] = “hello”;
// ngx_str_t mydata = {sizeof(mychar),mychar};
ngx_array_t *a = NULL;
a = ngx_array_create(pool, 1, sizeof(ngx_str_t));

ngx_str_t *s = ngx_array_push(a);
s->data = "hello";
s->len = sizeof(s->data);
printf("a->nelts: %ld, a->nalloc:%ld\n",a->nelts,a->nalloc);
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts))->data);
printf("ngx_array_push:%s\n",s->data);ngx_str_t *s1 = ngx_array_push(a);
s1->data = "wrold";
s1->len = sizeof(s1->data);
printf("a->nelts: %ld, a->nalloc:%ld\n",a->nelts,a->nalloc);
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts+sizeof(ngx_str_t)))->data);//地址加数据长度
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts)+1)->data); //使用指针加偏移
printf("ngx_array_push:%s\n",s1->data);ngx_str_t *s2 = ngx_array_push(a);
s2->data = "!";
s2->len = sizeof(s2->data);
printf("a->nelts: %ld, a->nalloc:%ld\n",a->nelts,a->nalloc);
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts+sizeof(ngx_str_t)*(a->nelts-1)))->data);//地址加数据长度
printf("ngx_array_push:%s\n",((ngx_str_t *)(a->elts)+a->nelts-1)->data); //使用指针加偏移
printf("ngx_array_push:%s\n",s2->data);print_pool(pool);ngx_destroy_pool(pool);return 0;

}

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