c - 地址越界

Question

crash --- cir_debug_log
cir_debug_log = $7 = {
buffer = 0xac3d83097f040056 <Address 0xac3d83097f040056 out of bounds>, 

crash --- print *cir_debug_log->buffer
Cannot access memory at address 0xac3d83097f040056
gdb: gdb request failed: print *cir_debug_log->buffer
crash ---

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这里定义了一个全局结构

typedef struct circular_buffer 

char            *buffer;
unsigned        capacity;
unsigned        head_offset;
unsigned        tail_offset;
volspin_t       vxl_lock;

extern struct circular_buffer cir_debug_log;

我正在初始化它的驱动程序加载时间，并在整个过程中跟踪它的地址，这不会改变。

cb->buffer : mzalloc_sleep(25000* sizeof(char));

但不知何故，我无法通过 CRASH 打印 cir_debug_log->buffer 中存在的字符串。它正确地复制了我检查过的这个缓冲区中的字符串。cb->buffer 的地址没有改变，但在崩溃时它显示不同的地址。

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cb_push_data: end trying to print messgae with cb->buffer contains buffer_content=
"Purging msg accumulated during reonline operation "

这是我的字符串，它也应该通过崩溃打印。

---

这是我的问题::

1. 我永远不会改变这个缓冲区的地址。出于存储目的，我正在使用尾部偏移量(像这样 *(cb->buffer + cb->tail_offset) = ch; 并像这样增加 tail_offset cb->tail_offset = (++cb->tail_offset)%cb->能力；

2. 我很好奇capacity，head_offset和tail_offset的内容。请查看崩溃 o/p。

崩溃——cir_debug_logcir_debug_log:$7:缓冲区——0xac3d83097f040056，容量——67131560，head_offset——2303465086，tail_offset——1156221409，vxl_lock -- 000

Answer 1

I see you have this code displayed, which is missing most of the initialization 
and what is displayed contains some syntax errors

typedef struct circular_buffer 
{ // this line is missing
char            *buffer;
unsigned        capacity;
unsigned        head_offset;
unsigned        tail_offset;
volspin_t       vxl_lock;
} // this line is missing

extern struct circular_buffer cir_debug_log;


// where is this declaration of 'cb'?
struct circular_buffer *cb = cir_debug_log; 

// where is the initialization of the other fields?
cb->capacity = 25000 * sizeof(char);
cb->head_offset = 0;
cd->tail_offset = 0;

// this has a syntax error: ':' should be '='
cb->buffer : mzalloc_sleep(25000* sizeof(char)); 


BTW:
it is normal to write to the *head* and read from the *tail*.