初始化一个NULL-terminated array of strings in C (以NULL结尾的字符串数组)

最新推荐文章于 2022-01-26 22:52:31 发布
原创 最新推荐文章于 2022-01-26 22:52:31 发布 · 2k 阅读 · 0 ·
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#null #c #google

我在调用一个开源库的时候发现参数是这样的：a NULL-terminated array of strings ，脑子一下转不过弯来，google后发现。。。

方法：const char *argv[] = {"foo", "bar", NULL };


可参考：http://stackoverflow.com/questions/2750846/correct-way-to-initialize-a-null-terminated-array-of-strings-in-c

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/* Copyright (c) 2009 Dave Gamble Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #ifndef cJSON__h #define cJSON__h #include <stddef.h> #ifdef __cplusplus extern "C" { #endif /* cJSON Types: */ #define cJSON_False 0 #define cJSON_True 1 #define cJSON_NULL 2 #define cJSON_Number 3 #define cJSON_String 4 #define cJSON_Array 5 #define cJSON_Object 6 #define cJSON_IsReference 256 #define cJSON_StringIsConst 512 /* The cJSON structure: */ typedef struct cJSON { struct cJSON *next,*prev; /* next/prev allow you to walk array/object chains. Alternatively, use GetArraySize/GetArrayItem/GetObjectItem */ struct cJSON *child; /* An array or object item will have a child pointer pointing to a chain of the items in the array/object. */ int type; /* The type of the item, as above. */ char *valuestring; /* The item's string, if type==cJSON_String */ int valueint; /* The item's number, if type==cJSON_Number */ double valuedouble; /* The item's number, if type==cJSON_Number */ char *string; /* The item's name string, if this item is the child of, or is in the list of subitems of an object. */ } cJSON; typedef struct cJSON_Hooks { void *(*malloc_fn)(size_t sz); void (*free_fn)(void *ptr); } cJSON_Hooks; /* Supply malloc, realloc and free functions to cJSON */ extern void cJSON_InitHooks(cJSON_Hooks* hooks); /* Supply a block of JSON, and this returns a cJSON object you can interrogate. Call cJSON_Delete when finished. */ extern cJSON *cJSON_Parse(const char *value); /* Render a cJSON entity to text for transfer/storage. Free the char* when finished. */ extern char *cJSON_Print(cJSON *item); /* Render a cJSON entity to text for transfer/storage without any formatting. Free the char* when finished. */ extern char *cJSON_PrintUnformatted(cJSON *item); /* Render a cJSON entity to text using a buffered strategy. prebuffer is a guess at the final size. guessing well reduces reallocation. fmt=0 gives unformatted, =1 gives formatted */ extern char *cJSON_PrintBuffered(cJSON *item,int prebuffer,int fmt); /* Delete a cJSON entity and all subentities. */ extern void cJSON_Delete(cJSON *c); /* Returns the number of items in an array (or object). */ extern int cJSON_GetArraySize(cJSON *array); /* Retrieve item number "item" from array "array". Returns NULL if unsuccessful. */ extern cJSON *cJSON_GetArrayItem(cJSON *array,int item); /* Get item "string" from object. Case insensitive. */ extern cJSON *cJSON_GetObjectItem(cJSON *object,const char *string); extern int cJSON_HasObjectItem(cJSON *object,const char *string); /* For analysing failed parses. This returns a pointer to the parse error. You'll probably need to look a few chars back to make sense of it. Defined when cJSON_Parse() returns 0. 0 when cJSON_Parse() succeeds. */ extern const char *cJSON_GetErrorPtr(void); /* These calls create a cJSON item of the appropriate type. */ extern cJSON *cJSON_CreateNull(void); extern cJSON *cJSON_CreateTrue(void); extern cJSON *cJSON_CreateFalse(void); extern cJSON *cJSON_CreateBool(int b); extern cJSON *cJSON_CreateNumber(double num); extern cJSON *cJSON_CreateString(const char *string); extern cJSON *cJSON_CreateArray(void); extern cJSON *cJSON_CreateObject(void); /* These utilities create an Array of count items. */ extern cJSON *cJSON_CreateIntArray(const int *numbers,int count); extern cJSON *cJSON_CreateFloatArray(const float *numbers,int count); extern cJSON *cJSON_CreateDoubleArray(const double *numbers,int count); extern cJSON *cJSON_CreateStringArray(const char **strings,int count); /* Append item to the specified array/object. */ extern void cJSON_AddItemToArray(cJSON *array, cJSON *item); extern void cJSON_AddItemToObject(cJSON *object,const char *string,cJSON *item); extern void cJSON_AddItemToObjectCS(cJSON *object,const char *string,cJSON *item); /* Use this when string is definitely const (i.e. a literal, or as good as), and will definitely survive the cJSON object */ /* Append reference to item to the specified array/object. Use this when you want to add an existing cJSON to a new cJSON, but don't want to corrupt your existing cJSON. */ extern void cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item); extern void cJSON_AddItemReferenceToObject(cJSON *object,const char *string,cJSON *item); /* Remove/Detatch items from Arrays/Objects. */ extern cJSON *cJSON_DetachItemFromArray(cJSON *array,int which); extern void cJSON_DeleteItemFromArray(cJSON *array,int which); extern cJSON *cJSON_DetachItemFromObject(cJSON *object,const char *string); extern void cJSON_DeleteItemFromObject(cJSON *object,const char *string); /* Update array items. */ extern void cJSON_InsertItemInArray(cJSON *array,int which,cJSON *newitem); /* Shifts pre-existing items to the right. */ extern void cJSON_ReplaceItemInArray(cJSON *array,int which,cJSON *newitem); extern void cJSON_ReplaceItemInObject(cJSON *object,const char *string,cJSON *newitem); /* Duplicate a cJSON item */ extern cJSON *cJSON_Duplicate(cJSON *item,int recurse); /* Duplicate will create a new, identical cJSON item to the one you pass, in new memory that will need to be released. With recurse!=0, it will duplicate any children connected to the item. The item->next and ->prev pointers are always zero on return from Duplicate. */ /* ParseWithOpts allows you to require (and check) that the JSON is null terminated, and to retrieve the pointer to the final byte parsed. */ extern cJSON *cJSON_ParseWithOpts(const char *value,const char **return_parse_end,int require_null_terminated); extern void cJSON_Minify(char *json); /* Macros for creating things quickly. */ #define cJSON_AddNullToObject(object,name) cJSON_AddItemToObject(object, name, cJSON_CreateNull()) #define cJSON_AddTrueToObject(object,name) cJSON_AddItemToObject(object, name, cJSON_CreateTrue()) #define cJSON_AddFalseToObject(object,name) cJSON_AddItemToObject(object, name, cJSON_CreateFalse()) #define cJSON_AddBoolToObject(object,name,b) cJSON_AddItemToObject(object, name, cJSON_CreateBool(b)) #define cJSON_AddNumberToObject(object,name,n) cJSON_AddItemToObject(object, name, cJSON_CreateNumber(n)) #define cJSON_AddStringToObject(object,name,s) cJSON_AddItemToObject(object, name, cJSON_CreateString(s)) /* When assigning an integer value, it needs to be propagated to valuedouble too. */ #define cJSON_SetIntValue(object,val) ((object)?(object)->valueint=(object)->valuedouble=(val):(val)) #define cJSON_SetNumberValue(object,val) ((object)?(object)->valueint=(object)->valuedouble=(val):(val)) /* Macro for iterating over an array */ #define cJSON_ArrayForEach(pos, head) for(pos = (head)->child; pos != NULL; pos = pos->next) #ifdef __cplusplus } #endif #endif /* Copyright (c) 2009 Dave Gamble Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /* cJSON */ /* JSON parser in C. */ #include <string.h> #include <stdio.h> #include <math.h> #include <stdlib.h> #include <float.h> #include <limits.h> #include <ctype.h> #include "cJSON.h" static const char *ep; const char *cJSON_GetErrorPtr(void) {return ep;} static int cJSON_strcasecmp(const char *s1,const char *s2) { if (!s1) return (s1==s2)?0:1;if (!s2) return 1; for(; tolower(*s1) == tolower(*s2); ++s1, ++s2) if(*s1 == 0) return 0; return tolower(*(const unsigned char *)s1) - tolower(*(const unsigned char *)s2); } static void *(*cJSON_malloc)(size_t sz) = malloc; static void (*cJSON_free)(void *ptr) = free; static char* cJSON_strdup(const char* str) { size_t len; char* copy; len = strlen(str) + 1; if (!(copy = (char*)cJSON_malloc(len))) return 0; memcpy(copy,str,len); return copy; } void cJSON_InitHooks(cJSON_Hooks* hooks) { if (!hooks) { /* Reset hooks */ cJSON_malloc = malloc; cJSON_free = free; return; } cJSON_malloc = (hooks->malloc_fn)?hooks->malloc_fn:malloc; cJSON_free = (hooks->free_fn)?hooks->free_fn:free; } /* Internal constructor. */ static cJSON *cJSON_New_Item(void) { cJSON* node = (cJSON*)cJSON_malloc(sizeof(cJSON)); if (node) memset(node,0,sizeof(cJSON)); return node; } /* Delete a cJSON structure. */ void cJSON_Delete(cJSON *c) { cJSON *next; while (c) { next=c->next; if (!(c->type&cJSON_IsReference) && c->child) cJSON_Delete(c->child); if (!(c->type&cJSON_IsReference) && c->valuestring) cJSON_free(c->valuestring); if (!(c->type&cJSON_StringIsConst) && c->string) cJSON_free(c->string); cJSON_free(c); c=next; } } /* Parse the input text to generate a number, and populate the result into item. */ static const char *parse_number(cJSON *item,const char *num) { double n=0,sign=1,scale=0;int subscale=0,signsubscale=1; if (*num=='-') sign=-1,num++; /* Has sign? */ if (*num=='0') num++; /* is zero */ if (*num>='1' && *num<='9') do n=(n*10.0)+(*num++ -'0'); while (*num>='0' && *num<='9'); /* Number? */ if (*num=='.' && num[1]>='0' && num[1]<='9') {num++; do n=(n*10.0)+(*num++ -'0'),scale--; while (*num>='0' && *num<='9');} /* Fractional part? */ if (*num=='e' || *num=='E') /* Exponent? */ { num++;if (*num=='+') num++; else if (*num=='-') signsubscale=-1,num++; /* With sign? */ while (*num>='0' && *num<='9') subscale=(subscale*10)+(*num++ - '0'); /* Number? */ } n=sign*n*pow(10.0,(scale+subscale*signsubscale)); /* number = +/- number.fraction * 10^+/- exponent */ item->valuedouble=n; item->valueint=(int)n; item->type=cJSON_Number; return num; } static int pow2gt (int x) { --x; x|=x>>1; x|=x>>2; x|=x>>4; x|=x>>8; x|=x>>16; return x+1; } typedef struct {char *buffer; int length; int offset; } printbuffer; static char* ensure(printbuffer *p,int needed) { char *newbuffer;int newsize; if (!p || !p->buffer) return 0; needed+=p->offset; if (needed<=p->length) return p->buffer+p->offset; newsize=pow2gt(needed); newbuffer=(char*)cJSON_malloc(newsize); if (!newbuffer) {cJSON_free(p->buffer);p->length=0,p->buffer=0;return 0;} if (newbuffer) memcpy(newbuffer,p->buffer,p->length); cJSON_free(p->buffer); p->length=newsize; p->buffer=newbuffer; return newbuffer+p->offset; } static int update(printbuffer *p) { char *str; if (!p || !p->buffer) return 0; str=p->buffer+p->offset; return p->offset+strlen(str); } /* Render the number nicely from the given item into a string. */ static char *print_number(cJSON *item,printbuffer *p) { char *str=0; double d=item->valuedouble; if (d==0) { if (p) str=ensure(p,2); else str=(char*)cJSON_malloc(2); /* special case for 0. */ if (str) strcpy(str,"0"); } else if (fabs(((double)item->valueint)-d)<=DBL_EPSILON && d<=INT_MAX && d>=INT_MIN) { if (p) str=ensure(p,21); else str=(char*)cJSON_malloc(21); /* 2^64+1 can be represented in 21 chars. */ if (str) sprintf(str,"%d",item->valueint); } else { if (p) str=ensure(p,64); else str=(char*)cJSON_malloc(64); /* This is a nice tradeoff. */ if (str) { if (fpclassify(d) != FP_ZERO && !isnormal(d)) sprintf(str,"null"); else if (fabs(floor(d)-d)<=DBL_EPSILON && fabs(d)<1.0e60) sprintf(str,"%.0f",d); else if (fabs(d)<1.0e-6 || fabs(d)>1.0e9) sprintf(str,"%e",d); else sprintf(str,"%f",d); } } return str; } static unsigned parse_hex4(const char *str) { unsigned h=0; if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0; h=h<<4;str++; if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0; h=h<<4;str++; if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0; h=h<<4;str++; if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0; return h; } /* Parse the input text into an unescaped cstring, and populate item. */ static const unsigned char firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC }; static const char *parse_string(cJSON *item,const char *str) { const char *ptr=str+1;char *ptr2;char *out;int len=0;unsigned uc,uc2; if (*str!='\"') {ep=str;return 0;} /* not a string! */ while (*ptr!='\"' && *ptr && ++len) if (*ptr++ == '\\') ptr++; /* Skip escaped quotes. */ out=(char*)cJSON_malloc(len+1); /* This is how long we need for the string, roughly. */ if (!out) return 0; ptr=str+1;ptr2=out; while (*ptr!='\"' && *ptr) { if (*ptr!='\\') *ptr2++=*ptr++; else { ptr++; switch (*ptr) { case 'b': *ptr2++='\b'; break; case 'f': *ptr2++='\f'; break; case 'n': *ptr2++='\n'; break; case 'r': *ptr2++='\r'; break; case 't': *ptr2++='\t'; break; case 'u': /* transcode utf16 to utf8. */ uc=parse_hex4(ptr+1);ptr+=4; /* get the unicode char. */ if ((uc>=0xDC00 && uc<=0xDFFF) || uc==0) break; /* check for invalid. */ if (uc>=0xD800 && uc<=0xDBFF) /* UTF16 surrogate pairs. */ { if (ptr[1]!='\\' || ptr[2]!='u') break; /* missing second-half of surrogate. */ uc2=parse_hex4(ptr+3);ptr+=6; if (uc2<0xDC00 || uc2>0xDFFF) break; /* invalid second-half of surrogate. */ uc=0x10000 + (((uc&0x3FF)<<10) | (uc2&0x3FF)); } len=4;if (uc<0x80) len=1;else if (uc<0x800) len=2;else if (uc<0x10000) len=3; ptr2+=len; switch (len) { case 4: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6; case 3: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6; case 2: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6; case 1: *--ptr2 =(uc | firstByteMark[len]); } ptr2+=len; break; default: *ptr2++=*ptr; break; } ptr++; } } *ptr2=0; if (*ptr=='\"') ptr++; item->valuestring=out; item->type=cJSON_String; return ptr; } /* Render the cstring provided to an escaped version that can be printed. */ static char *print_string_ptr(const char *str,printbuffer *p) { const char *ptr;char *ptr2,*out;int len=0,flag=0;unsigned char token; for (ptr=str;*ptr;ptr++) flag|=((*ptr>0 && *ptr<32)||(*ptr=='\"')||(*ptr=='\\'))?1:0; if (!flag) { len=ptr-str; if (p) out=ensure(p,len+3); else out=(char*)cJSON_malloc(len+3); if (!out) return 0; ptr2=out;*ptr2++='\"'; strcpy(ptr2,str); ptr2[len]='\"'; ptr2[len+1]=0; return out; } if (!str) { if (p) out=ensure(p,3); else out=(char*)cJSON_malloc(3); if (!out) return 0; strcpy(out,"\"\""); return out; } ptr=str;while ((token=*ptr) && ++len) {if (strchr("\"\\\b\f\n\r\t",token)) len++; else if (token<32) len+=5;ptr++;} if (p) out=ensure(p,len+3); else out=(char*)cJSON_malloc(len+3); if (!out) return 0; ptr2=out;ptr=str; *ptr2++='\"'; while (*ptr) { if ((unsigned char)*ptr>31 && *ptr!='\"' && *ptr!='\\') *ptr2++=*ptr++; else { *ptr2++='\\'; switch (token=*ptr++) { case '\\': *ptr2++='\\'; break; case '\"': *ptr2++='\"'; break; case '\b': *ptr2++='b'; break; case '\f': *ptr2++='f'; break; case '\n': *ptr2++='n'; break; case '\r': *ptr2++='r'; break; case '\t': *ptr2++='t'; break; default: sprintf(ptr2,"u%04x",token);ptr2+=5; break; /* escape and print */ } } } *ptr2++='\"';*ptr2++=0; return out; } /* Invote print_string_ptr (which is useful) on an item. */ static char *print_string(cJSON *item,printbuffer *p) {return print_string_ptr(item->valuestring,p);} /* Predeclare these prototypes. */ static const char *parse_value(cJSON *item,const char *value); static char *print_value(cJSON *item,int depth,int fmt,printbuffer *p); static const char *parse_array(cJSON *item,const char *value); static char *print_array(cJSON *item,int depth,int fmt,printbuffer *p); static const char *parse_object(cJSON *item,const char *value); static char *print_object(cJSON *item,int depth,int fmt,printbuffer *p); /* Utility to jump whitespace and cr/lf */ static const char *skip(const char *in) {while (in && *in && (unsigned char)*in<=32) in++; return in;} /* Parse an object - create a new root, and populate. */ cJSON *cJSON_ParseWithOpts(const char *value,const char **return_parse_end,int require_null_terminated) { const char *end=0; cJSON *c=cJSON_New_Item(); ep=0; if (!c) return 0; /* memory fail */ end=parse_value(c,skip(value)); if (!end) {cJSON_Delete(c);return 0;} /* parse failure. ep is set. */ /* if we require null-terminated JSON without appended garbage, skip and then check for a null terminator */ if (require_null_terminated) {end=skip(end);if (*end) {cJSON_Delete(c);ep=end;return 0;}} if (return_parse_end) *return_parse_end=end; return c; } /* Default options for cJSON_Parse */ cJSON *cJSON_Parse(const char *value) {return cJSON_ParseWithOpts(value,0,0);} /* Render a cJSON item/entity/structure to text. */ char *cJSON_Print(cJSON *item) {return print_value(item,0,1,0);} char *cJSON_PrintUnformatted(cJSON *item) {return print_value(item,0,0,0);} char *cJSON_PrintBuffered(cJSON *item,int prebuffer,int fmt) { printbuffer p; p.buffer=(char*)cJSON_malloc(prebuffer); p.length=prebuffer; p.offset=0; return print_value(item,0,fmt,&p); return p.buffer; } /* Parser core - when encountering text, process appropriately. */ static const char *parse_value(cJSON *item,const char *value) { if (!value) return 0; /* Fail on null. */ if (!strncmp(value,"null",4)) { item->type=cJSON_NULL; return value+4; } if (!strncmp(value,"false",5)) { item->type=cJSON_False; return value+5; } if (!strncmp(value,"true",4)) { item->type=cJSON_True; item->valueint=1; return value+4; } if (*value=='\"') { return parse_string(item,value); } if (*value=='-' || (*value>='0' && *value<='9')) { return parse_number(item,value); } if (*value=='[') { return parse_array(item,value); } if (*value=='{') { return parse_object(item,value); } ep=value;return 0; /* failure. */ } /* Render a value to text. */ static char *print_value(cJSON *item,int depth,int fmt,printbuffer *p) { char *out=0; if (!item) return 0; if (p) { switch ((item->type)&255) { case cJSON_NULL: {out=ensure(p,5); if (out) strcpy(out,"null"); break;} case cJSON_False: {out=ensure(p,6); if (out) strcpy(out,"false"); break;} case cJSON_True: {out=ensure(p,5); if (out) strcpy(out,"true"); break;} case cJSON_Number: out=print_number(item,p);break; case cJSON_String: out=print_string(item,p);break; case cJSON_Array: out=print_array(item,depth,fmt,p);break; case cJSON_Object: out=print_object(item,depth,fmt,p);break; } } else { switch ((item->type)&255) { case cJSON_NULL: out=cJSON_strdup("null"); break; case cJSON_False: out=cJSON_strdup("false");break; case cJSON_True: out=cJSON_strdup("true"); break; case cJSON_Number: out=print_number(item,0);break; case cJSON_String: out=print_string(item,0);break; case cJSON_Array: out=print_array(item,depth,fmt,0);break; case cJSON_Object: out=print_object(item,depth,fmt,0);break; } } return out; } /* Build an array from input text. */ static const char *parse_array(cJSON *item,const char *value) { cJSON *child; if (*value!='[') {ep=value;return 0;} /* not an array! */ item->type=cJSON_Array; value=skip(value+1); if (*value==']') return value+1; /* empty array. */ item->child=child=cJSON_New_Item(); if (!item->child) return 0; /* memory fail */ value=skip(parse_value(child,skip(value))); /* skip any spacing, get the value. */ if (!value) return 0; while (*value==',') { cJSON *new_item; if (!(new_item=cJSON_New_Item())) return 0; /* memory fail */ child->next=new_item;new_item->prev=child;child=new_item; value=skip(parse_value(child,skip(value+1))); if (!value) return 0; /* memory fail */ } if (*value==']') return value+1; /* end of array */ ep=value;return 0; /* malformed. */ } /* Render an array to text */ static char *print_array(cJSON *item,int depth,int fmt,printbuffer *p) { char **entries; char *out=0,*ptr,*ret;int len=5; cJSON *child=item->child; int numentries=0,i=0,fail=0; size_t tmplen=0; /* How many entries in the array? */ while (child) numentries++,child=child->next; /* Explicitly handle numentries==0 */ if (!numentries) { if (p) out=ensure(p,3); else out=(char*)cJSON_malloc(3); if (out) strcpy(out,"[]"); return out; } if (p) { /* Compose the output array. */ i=p->offset; ptr=ensure(p,1);if (!ptr) return 0; *ptr='['; p->offset++; child=item->child; while (child && !fail) { print_value(child,depth+1,fmt,p); p->offset=update(p); if (child->next) {len=fmt?2:1;ptr=ensure(p,len+1);if (!ptr) return 0;*ptr++=',';if(fmt)*ptr++=' ';*ptr=0;p->offset+=len;} child=child->next; } ptr=ensure(p,2);if (!ptr) return 0; *ptr++=']';*ptr=0; out=(p->buffer)+i; } else { /* Allocate an array to hold the values for each */ entries=(char**)cJSON_malloc(numentries*sizeof(char*)); if (!entries) return 0; memset(entries,0,numentries*sizeof(char*)); /* Retrieve all the results: */ child=item->child; while (child && !fail) { ret=print_value(child,depth+1,fmt,0); entries[i++]=ret; if (ret) len+=strlen(ret)+2+(fmt?1:0); else fail=1; child=child->next; } /* If we didn't fail, try to malloc the output string */ if (!fail) out=(char*)cJSON_malloc(len); /* If that fails, we fail. */ if (!out) fail=1; /* Handle failure. */ if (fail) { for (i=0;i<numentries;i++) if (entries[i]) cJSON_free(entries[i]); cJSON_free(entries); return 0; } /* Compose the output array. */ *out='['; ptr=out+1;*ptr=0; for (i=0;i<numentries;i++) { tmplen=strlen(entries[i]);memcpy(ptr,entries[i],tmplen);ptr+=tmplen; if (i!=numentries-1) {*ptr++=',';if(fmt)*ptr++=' ';*ptr=0;} cJSON_free(entries[i]); } cJSON_free(entries); *ptr++=']';*ptr++=0; } return out; } /* Build an object from the text. */ static const char *parse_object(cJSON *item,const char *value) { cJSON *child; if (*value!='{') {ep=value;return 0;} /* not an object! */ item->type=cJSON_Object; value=skip(value+1); if (*value=='}') return value+1; /* empty array. */ item->child=child=cJSON_New_Item(); if (!item->child) return 0; value=skip(parse_string(child,skip(value))); if (!value) return 0; child->string=child->valuestring;child->valuestring=0; if (*value!=':') {ep=value;return 0;} /* fail! */ value=skip(parse_value(child,skip(value+1))); /* skip any spacing, get the value. */ if (!value) return 0; while (*value==',') { cJSON *new_item; if (!(new_item=cJSON_New_Item())) return 0; /* memory fail */ child->next=new_item;new_item->prev=child;child=new_item; value=skip(parse_string(child,skip(value+1))); if (!value) return 0; child->string=child->valuestring;child->valuestring=0; if (*value!=':') {ep=value;return 0;} /* fail! */ value=skip(parse_value(child,skip(value+1))); /* skip any spacing, get the value. */ if (!value) return 0; } if (*value=='}') return value+1; /* end of array */ ep=value;return 0; /* malformed. */ } /* Render an object to text. */ static char *print_object(cJSON *item,int depth,int fmt,printbuffer *p) { char **entries=0,**names=0; char *out=0,*ptr,*ret,*str;int len=7,i=0,j; cJSON *child=item->child; int numentries=0,fail=0; size_t tmplen=0; /* Count the number of entries. */ while (child) numentries++,child=child->next; /* Explicitly handle empty object case */ if (!numentries) { if (p) out=ensure(p,fmt?depth+4:3); else out=(char*)cJSON_malloc(fmt?depth+4:3); if (!out) return 0; ptr=out;*ptr++='{'; if (fmt) {*ptr++='\n';for (i=0;i<depth-1;i++) *ptr++='\t';} *ptr++='}';*ptr++=0; return out; } if (p) { /* Compose the output: */ i=p->offset; len=fmt?2:1; ptr=ensure(p,len+1); if (!ptr) return 0; *ptr++='{'; if (fmt) *ptr++='\n'; *ptr=0; p->offset+=len; child=item->child;depth++; while (child) { if (fmt) { ptr=ensure(p,depth); if (!ptr) return 0; for (j=0;j<depth;j++) *ptr++='\t'; p->offset+=depth; } print_string_ptr(child->string,p); p->offset=update(p); len=fmt?2:1; ptr=ensure(p,len); if (!ptr) return 0; *ptr++=':';if (fmt) *ptr++='\t'; p->offset+=len; print_value(child,depth,fmt,p); p->offset=update(p); len=(fmt?1:0)+(child->next?1:0); ptr=ensure(p,len+1); if (!ptr) return 0; if (child->next) *ptr++=','; if (fmt) *ptr++='\n';*ptr=0; p->offset+=len; child=child->next; } ptr=ensure(p,fmt?(depth+1):2); if (!ptr) return 0; if (fmt) for (i=0;i<depth-1;i++) *ptr++='\t'; *ptr++='}';*ptr=0; out=(p->buffer)+i; } else { /* Allocate space for the names and the objects */ entries=(char**)cJSON_malloc(numentries*sizeof(char*)); if (!entries) return 0; names=(char**)cJSON_malloc(numentries*sizeof(char*)); if (!names) {cJSON_free(entries);return 0;} memset(entries,0,sizeof(char*)*numentries); memset(names,0,sizeof(char*)*numentries); /* Collect all the results into our arrays: */ child=item->child;depth++;if (fmt) len+=depth; while (child && !fail) { names[i]=str=print_string_ptr(child->string,0); entries[i++]=ret=print_value(child,depth,fmt,0); if (str && ret) len+=strlen(ret)+strlen(str)+2+(fmt?2+depth:0); else fail=1; child=child->next; } /* Try to allocate the output string */ if (!fail) out=(char*)cJSON_malloc(len); if (!out) fail=1; /* Handle failure */ if (fail) { for (i=0;i<numentries;i++) {if (names[i]) cJSON_free(names[i]);if (entries[i]) cJSON_free(entries[i]);} cJSON_free(names);cJSON_free(entries); return 0; } /* Compose the output: */ *out='{';ptr=out+1;if (fmt)*ptr++='\n';*ptr=0; for (i=0;i<numentries;i++) { if (fmt) for (j=0;j<depth;j++) *ptr++='\t'; tmplen=strlen(names[i]);memcpy(ptr,names[i],tmplen);ptr+=tmplen; *ptr++=':';if (fmt) *ptr++='\t'; strcpy(ptr,entries[i]);ptr+=strlen(entries[i]); if (i!=numentries-1) *ptr++=','; if (fmt) *ptr++='\n';*ptr=0; cJSON_free(names[i]);cJSON_free(entries[i]); } cJSON_free(names);cJSON_free(entries); if (fmt) for (i=0;i<depth-1;i++) *ptr++='\t'; *ptr++='}';*ptr++=0; } return out; } /* Get Array size/item / object item. */ int cJSON_GetArraySize(cJSON *array) {cJSON *c=array->child;int i=0;while(c)i++,c=c->next;return i;} cJSON *cJSON_GetArrayItem(cJSON *array,int item) {cJSON *c=array->child; while (c && item>0) item--,c=c->next; return c;} cJSON *cJSON_GetObjectItem(cJSON *object,const char *string) {cJSON *c=object->child; while (c && cJSON_strcasecmp(c->string,string)) c=c->next; return c;} int cJSON_HasObjectItem(cJSON *object,const char *string) { cJSON *c=object->child; while (c ) { if(cJSON_strcasecmp(c->string,string)==0){ return 1; } c=c->next; } return 0; } /* Utility for array list handling. */ static void suffix_object(cJSON *prev,cJSON *item) {prev->next=item;item->prev=prev;} /* Utility for handling references. */ static cJSON *create_reference(cJSON *item) {cJSON *ref=cJSON_New_Item();if (!ref) return 0;memcpy(ref,item,sizeof(cJSON));ref->string=0;ref->type|=cJSON_IsReference;ref->next=ref->prev=0;return ref;} /* Add item to array/object. */ void cJSON_AddItemToArray(cJSON *array, cJSON *item) {cJSON *c=array->child;if (!item) return; if (!c) {array->child=item;} else {while (c && c->next) c=c->next; suffix_object(c,item);}} void cJSON_AddItemToObject(cJSON *object,const char *string,cJSON *item) {if (!item) return; if (item->string) cJSON_free(item->string);item->string=cJSON_strdup(string);cJSON_AddItemToArray(object,item);} void cJSON_AddItemToObjectCS(cJSON *object,const char *string,cJSON *item) {if (!item) return; if (!(item->type&cJSON_StringIsConst) && item->string) cJSON_free(item->string);item->string=(char*)string;item->type|=cJSON_StringIsConst;cJSON_AddItemToArray(object,item);} void cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item) {cJSON_AddItemToArray(array,create_reference(item));} void cJSON_AddItemReferenceToObject(cJSON *object,const char *string,cJSON *item) {cJSON_AddItemToObject(object,string,create_reference(item));} cJSON *cJSON_DetachItemFromArray(cJSON *array,int which) {cJSON *c=array->child;while (c && which>0) c=c->next,which--;if (!c) return 0; if (c->prev) c->prev->next=c->next;if (c->next) c->next->prev=c->prev;if (c==array->child) array->child=c->next;c->prev=c->next=0;return c;} void cJSON_DeleteItemFromArray(cJSON *array,int which) {cJSON_Delete(cJSON_DetachItemFromArray(array,which));} cJSON *cJSON_DetachItemFromObject(cJSON *object,const char *string) {int i=0;cJSON *c=object->child;while (c && cJSON_strcasecmp(c->string,string)) i++,c=c->next;if (c) return cJSON_DetachItemFromArray(object,i);return 0;} void cJSON_DeleteItemFromObject(cJSON *object,const char *string) {cJSON_Delete(cJSON_DetachItemFromObject(object,string));} /* Replace array/object items with new ones. */ void cJSON_InsertItemInArray(cJSON *array,int which,cJSON *newitem) {cJSON *c=array->child;while (c && which>0) c=c->next,which--;if (!c) {cJSON_AddItemToArray(array,newitem);return;} newitem->next=c;newitem->prev=c->prev;c->prev=newitem;if (c==array->child) array->child=newitem; else newitem->prev->next=newitem;} void cJSON_ReplaceItemInArray(cJSON *array,int which,cJSON *newitem) {cJSON *c=array->child;while (c && which>0) c=c->next,which--;if (!c) return; newitem->next=c->next;newitem->prev=c->prev;if (newitem->next) newitem->next->prev=newitem; if (c==array->child) array->child=newitem; else newitem->prev->next=newitem;c->next=c->prev=0;cJSON_Delete(c);} void cJSON_ReplaceItemInObject(cJSON *object,const char *string,cJSON *newitem){int i=0;cJSON *c=object->child;while(c && cJSON_strcasecmp(c->string,string))i++,c=c->next;if(c){newitem->string=cJSON_strdup(string);cJSON_ReplaceItemInArray(object,i,newitem);}} /* Create basic types: */ cJSON *cJSON_CreateNull(void) {cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_NULL;return item;} cJSON *cJSON_CreateTrue(void) {cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_True;return item;} cJSON *cJSON_CreateFalse(void) {cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_False;return item;} cJSON *cJSON_CreateBool(int b) {cJSON *item=cJSON_New_Item();if(item)item->type=b?cJSON_True:cJSON_False;return item;} cJSON *cJSON_CreateNumber(double num) {cJSON *item=cJSON_New_Item();if(item){item->type=cJSON_Number;item->valuedouble=num;item->valueint=(int)num;}return item;} cJSON *cJSON_CreateString(const char *string) {cJSON *item=cJSON_New_Item();if(item){item->type=cJSON_String;item->valuestring=cJSON_strdup(string);}return item;} cJSON *cJSON_CreateArray(void) {cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_Array;return item;} cJSON *cJSON_CreateObject(void) {cJSON *item=cJSON_New_Item();if(item)item->type=cJSON_Object;return item;} /* Create Arrays: */ cJSON *cJSON_CreateIntArray(const int *numbers,int count) {int i;cJSON *n=0,*p=0,*a=cJSON_CreateArray();for(i=0;a && i<count;i++){n=cJSON_CreateNumber(numbers[i]);if(!i)a->child=n;else suffix_object(p,n);p=n;}return a;} cJSON *cJSON_CreateFloatArray(const float *numbers,int count) {int i;cJSON *n=0,*p=0,*a=cJSON_CreateArray();for(i=0;a && i<count;i++){n=cJSON_CreateNumber(numbers[i]);if(!i)a->child=n;else suffix_object(p,n);p=n;}return a;} cJSON *cJSON_CreateDoubleArray(const double *numbers,int count) {int i;cJSON *n=0,*p=0,*a=cJSON_CreateArray();for(i=0;a && i<count;i++){n=cJSON_CreateNumber(numbers[i]);if(!i)a->child=n;else suffix_object(p,n);p=n;}return a;} cJSON *cJSON_CreateStringArray(const char **strings,int count) {int i;cJSON *n=0,*p=0,*a=cJSON_CreateArray();for(i=0;a && i<count;i++){n=cJSON_CreateString(strings[i]);if(!i)a->child=n;else suffix_object(p,n);p=n;}return a;} /* Duplication */ cJSON *cJSON_Duplicate(cJSON *item,int recurse) { cJSON *newitem,*cptr,*nptr=0,*newchild; /* Bail on bad ptr */ if (!item) return 0; /* Create new item */ newitem=cJSON_New_Item(); if (!newitem) return 0; /* Copy over all vars */ newitem->type=item->type&(~cJSON_IsReference),newitem->valueint=item->valueint,newitem->valuedouble=item->valuedouble; if (item->valuestring) {newitem->valuestring=cJSON_strdup(item->valuestring); if (!newitem->valuestring) {cJSON_Delete(newitem);return 0;}} if (item->string) {newitem->string=cJSON_strdup(item->string); if (!newitem->string) {cJSON_Delete(newitem);return 0;}} /* If non-recursive, then we're done! */ if (!recurse) return newitem; /* Walk the ->next chain for the child. */ cptr=item->child; while (cptr) { newchild=cJSON_Duplicate(cptr,1); /* Duplicate (with recurse) each item in the ->next chain */ if (!newchild) {cJSON_Delete(newitem);return 0;} if (nptr) {nptr->next=newchild,newchild->prev=nptr;nptr=newchild;} /* If newitem->child already set, then crosswire ->prev and ->next and move on */ else {newitem->child=newchild;nptr=newchild;} /* Set newitem->child and move to it */ cptr=cptr->next; } return newitem; } void cJSON_Minify(char *json) { char *into=json; while (*json) { if (*json==' ') json++; else if (*json=='\t') json++; /* Whitespace characters. */ else if (*json=='\r') json++; else if (*json=='\n') json++; else if (*json=='/' && json[1]=='/') while (*json && *json!='\n') json++; /* double-slash comments, to end of line. */ else if (*json=='/' && json[1]=='*') {while (*json && !(*json=='*' && json[1]=='/')) json++;json+=2;} /* multiline comments. */ else if (*json=='\"'){*into++=*json++;while (*json && *json!='\"'){if (*json=='\\') *into++=*json++;*into++=*json++;}*into++=*json++;} /* string literals, which are \" sensitive. */ else *into++=*json++; /* All other characters. */ } *into=0; /* and null-terminate. */ } #include <stdio.h> #include <stdlib.h> #include <string.h> #include <cJSON.h> // 引入 cJSON 头文件 #include "MQTTClient.h" #define ADDRESS "tcp://192.168.12.53:1883" #define CLIENTID "C_Subscriber" #define TOPIC "control/led" // 必须和 Qt 发送的主题一致！ #define QOS 1 #define TIMEOUT 10000L volatile MQTTClient_deliveryToken deliveredtoken; void delivered(void *context, MQTTClient_deliveryToken dt) { printf("Message with token %d confirmed\n", dt); deliveredtoken = dt; } void connlost(void *context, char *cause) { printf("Connection lost: %s\n", cause); } int msgarrvd(void *context, char *topicName, int topicLen, MQTTClient_message *message) { // 提取 payload char* payload = (char*)message->payload; int len = message->payloadlen; printf("【消息到达】\n"); printf(" 主题: %.*s\n", topicLen, topicName); printf(" 内容: %.*s\n", len, payload); // 将 payload 转为以 '\0' 结尾的字符串用于解析 JSON char* jsonStr = (char*)malloc(len + 1); if (!jsonStr) { printf("内存分配失败\n"); goto cleanup; } memcpy(jsonStr, payload, len); jsonStr[len] = '\0'; // 解析 JSON cJSON *root = cJSON_Parse(jsonStr); if (!root) { printf("JSON 解析失败: %s\n", cJSON_GetErrorPtr()); free(jsonStr); goto cleanup; } cJSON *device = cJSON_GetObjectItem(root, "device"); cJSON *status = cJSON_GetObjectItem(root, "status"); if (device && cJSON_IsString(device) && status && cJSON_IsString(status)) { if (strcmp(device->valuestring, "led") == 0) { if (strcmp(status->valuestring, "on") == 0) { printf("✅ 操作执行：LED 已开启\n"); } else if (strcmp(status->valuestring, "off") == 0) { printf("🛑 操作执行：LED 已关闭\n"); } else { printf("⚠️ 未知状态: %s\n", status->valuestring); } } else { printf("💡 设备不支持: %s\n", device->valuestring); } } else { printf("❌ JSON 缺少必要字段 (device/status)\n"); } cJSON_Delete(root); // 释放 cJSON 对象 free(jsonStr); cleanup: MQTTClient_freeMessage(&message); MQTTClient_free(topicName); return 1; } int main(int argc, char* argv[]) { MQTTClient client; MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer; int rc; int ch; // 创建客户端（注意 persistence 设置为 NULL） MQTTClient_create(&client, ADDRESS, CLIENTID, MQTTCLIENT_PERSISTENCE_NONE, NULL); conn_opts.keepAliveInterval = 20; conn_opts.cleansession = 1; // 注册回调函数 MQTTClient_setCallbacks(client, NULL, connlost, msgarrvd, delivered); // 连接 Broker if ((rc = MQTTClient_connect(client, &conn_opts)) != MQTTCLIENT_SUCCESS) { printf("连接失败，返回码: %d\n", rc); exit(EXIT_FAILURE); } printf("正在订阅主题: %s\n", TOPIC); printf("等待来自 Qt 的 LED 控制指令...\n"); printf("按 Q + Enter 退出程序\n\n"); // 订阅主题 MQTTClient_subscribe(client, TOPIC, QOS); // 等待用户输入 Q 退出 do { ch = getchar(); } while(ch != 'Q' && ch != 'q'); // 清理资源 MQTTClient_unsubscribe(client, TOPIC); MQTTClient_disconnect(client, TIMEOUT); MQTTClient_destroy(&client); return rc; } 这样写对吗
最新发布
11-01
- `MQTTClient_message *message` 是一个输入参数，由 Paho 内部管理，你在回调中 **不能手动 free 它们**！ - 同样，`topicName` 也是由库提供的内存，不需要也不应该 `MQTTClient_free()`。 - 正确做法是：让 Paho...
char* filename_completion_function(const char* text, int state) { static DIR* dir = NULL; static char *filename = NULL, *dirname = NULL; static size_t filename_len = 0; static int is_virtual = 0; static char virtual_prefix[32] = ""; struct dirent *entry; char* temp; size_t len; if (state == 0 || dir == NULL) { if (dir != NULL) { closedir(dir); dir = NULL; } // 重置虚拟路径状态 is_virtual = 0; virtual_prefix[0] = '\0'; // 解析虚拟路径 char resolved_path[PATH_MAX]; int temp_is_virtual = 0; resolve_virtual_path(text, resolved_path, sizeof(resolved_path), &temp_is_virtual); // 如果是虚拟路径，保存原始前缀 if (temp_is_virtual) { is_virtual = 1; // 提取虚拟路径前缀（如"flash:/etc"） const char* end = strrchr(text, '/'); if (end) { size_t prefix_len = end - text + 1; // 包含最后一个斜杠 strncpy(virtual_prefix, text, prefix_len); virtual_prefix[prefix_len] = '\0'; } else { strcpy(virtual_prefix, text); } } // 使用解析后的路径进行后续处理 const char* process_text = temp_is_virtual ? resolved_path : text; char* last_slash = strrchr(process_text, '/'); if (last_slash) { last_slash++; filename = XREALLOC(MTYPE_TMP, filename, strlen(last_slash) + 1); strcpy(filename, last_slash); len = last_slash - process_text; dirname = XREALLOC(MTYPE_TMP, dirname, len + 1); strncpy(dirname, process_text, len); dirname[len] = '\0'; } else { filename = XSTRDUP(MTYPE_TMP, process_text); dirname = NULL; } /* support for ``~user'' syntax */ if (dirname && *dirname == '~') { temp = tilde_expand(dirname); dirname = XREALLOC(MTYPE_TMP, dirname, strlen(temp) + 1); (void)strcpy(dirname, temp); /* safe */ XFREE(0, temp); /* no longer needed */ } /* will be used in cycle */ filename_len = strlen(filename); if (filename_len == 0) return (NULL); /* no expansion possible */ dir = opendir(dirname ? dirname : "."); if (!dir) return (NULL); /* cannot open the directory */ } /* find the match */ while ((entry = readdir(dir)) != NULL) { /* otherwise, get first entry where first */ /* filename_len characters are equal */ if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0) { continue; } if (entry->d_name[0] == '.') { continue; } if (entry->d_type == DT_LNK) { continue; } if (entry->d_name[0] == filename[0] #if defined(__SVR4) || defined(linux) && strlen(entry->d_name) >= filename_len #else && entry->d_namlen >= filename_len #endif && strncmp(entry->d_name, filename, filename_len) == 0) break; } if (entry) { /* match found */ struct stat stbuf; #if defined(__SVR4) || defined(linux) len = strlen(entry->d_name) + #else len = entry->d_namlen + #endif ((dirname) ? strlen(dirname) : 0) + 1 + 1; temp = XMALLOC(MTYPE_TMP, len); (void)sprintf(temp, "%s%s", dirname ? dirname : "", entry->d_name); /* safe */ // 如果是目录，添加斜杠 if (stat(temp, &stbuf) == 0 && S_ISDIR(stbuf.st_mode)) { temp = XREALLOC(MTYPE_TMP, temp, len + 2); strcat(temp, "/"); } // 如果是虚拟路径，转换回原始格式 if (is_virtual) { // 计算真实路径前缀长度 size_t real_prefix_len = strlen(dirname ? dirname : ""); // 只保留文件名部分 const char* file_part = temp + real_prefix_len; // 重建虚拟路径：虚拟前缀 + 文件名 char* new_temp = XMALLOC(MTYPE_TMP, strlen(virtual_prefix) + strlen(file_part) + 1); sprintf(new_temp, "%s%s", virtual_prefix, file_part); XFREE(MTYPE_TMP, temp); temp = new_temp; } } else { temp = NULL; } printf("\n temp = '%s'\n", temp); return (temp); } 至于刚才说的第一个问题，显示会多路径，这里无法修改的，如果改了这里的话，那readline获取的就没有目录了，就会出现下边的情况： <dahua>dir etc/n temp = 'nos.conf' temp = 'nos.conf.back' temp = 'nos.conf.bak' temp = '(null)' nos.conf temp = '(null)' <dahua>dir nos.conf temp = '(null)' <dahua>dir nos.conf temp = '(null)' <dahua>dir nos.conf temp = '(null)' <dahua> 连续tab补全会从dir etc/nos.conf直接变成dir nos.conf，目录直接消失了，这是有问题的，路径都被改了 下边的上层调用函数： char** cmlsh_completion(char* text, int start, int end) { char** matches; char** filename_matches = NULL; int is_fs_command = 0; int fs_cmd_len = 0; int i; // 获取当前行信息 const LineInfo* li; li = el_line(e); rl_line_buffer = (char*)li->buffer; rl_end = li->lastchar - li->buffer; rl_line_buffer[rl_end] = '\0'; // 初始补全尝试 matches = completion_matches(text, cmlsh_completion_matches); // 检查是否是文件系统命令 for (i = 0; cmlsh_fs_commands[i]; i++) { int len = strlen(cmlsh_fs_commands[i]); if (strncmp(rl_line_buffer, cmlsh_fs_commands[i], len) == 0 && (rl_line_buffer[len] == ' ' || rl_line_buffer[len] == '\0')) { is_fs_command = 1; fs_cmd_len = len; break; } } size_t text_len = strlen(text); // 如果是文件系统命令且输入以/结尾，尝试自动列出目录内容 if (is_fs_command && start > fs_cmd_len && text_len > 0 && text[text_len - 1] == '/') { char cwd[PATH_MAX]; if (!getcwd(cwd, sizeof(cwd))) strcpy(cwd, "."); char fullpath[PATH_MAX]; int is_virtual = 0; char resolved_text[PATH_MAX]; // 解析虚拟路径 resolve_virtual_path(text, resolved_text, sizeof(resolved_text), &is_virtual); if (is_virtual) { snprintf(fullpath, sizeof(fullpath), "%s", resolved_text); } else { snprintf(fullpath, sizeof(fullpath), "%s/%.*s", cwd, (int)(text_len - 1), text); } // 确保路径以/结尾 int fullpath_len = strlen(fullpath); if (fullpath_len > 0 && fullpath[fullpath_len - 1] != '/') { if (fullpath_len < sizeof(fullpath) - 1) { strcat(fullpath, "/"); } } struct stat st; if (stat(fullpath, &st) == 0 && S_ISDIR(st.st_mode)) { int count = 0, max_len = 0; char** sub_matches = list_directory_entries(fullpath, &count, &max_len); if (sub_matches && count > 0) { rl_display_match_list_tmp(sub_matches, count, max_len); for (int i = 0; i < count; i++) XFREE(MTYPE_TMP, sub_matches[i]); XFREE(MTYPE_TMP, sub_matches); return NULL; } } } // 命令补全失败 → 尝试文件名补全 if (!matches || !matches[0]) { // 清理之前的匹配结果 if (matches) { for (i = 0; matches[i]; i++) XFREE(MTYPE_TMP, matches[i]); XFREE(MTYPE_TMP, matches); matches = NULL; } // 如果是文件系统命令，获取文件名补全 if (is_fs_command && start > fs_cmd_len) { filename_matches = completion_matches(text, filename_completion_function); } //int is_flash_prefix = (strncmp(NOS_CMLSH_FLASH_DIR, text, strlen(text)) == 0) && (strlen(text) < strlen(NOS_CMLSH_FLASH_DIR)); // ========== 虚拟路径前缀匹配处理 ========== const char* virtual_prefix = "flash:/"; size_t virtual_prefix_len = strlen(virtual_prefix); // 检查输入是否匹配虚拟路径前缀 int should_add_virtual = 0; if (strncmp(text, virtual_prefix, text_len) == 0) { // 完全匹配前缀 should_add_virtual = 1; } else if (text_len < virtual_prefix_len && strncmp(virtual_prefix, text, text_len) == 0) { // 部分匹配前缀（如"f"、"fl"等） should_add_virtual = 1; } // 检查是否已经包含虚拟路径项 int virtual_already_exists = 0; if (filename_matches) { for (i = 0; filename_matches[i]; i++) { if (strcmp(filename_matches[i], virtual_prefix) == 0) { virtual_already_exists = 1; break; } } } // 如果需要添加虚拟路径项且尚未存在 if (should_add_virtual && !virtual_already_exists) { int real_count = 0; if (filename_matches) { while (filename_matches[real_count]) real_count++; } // 创建新数组（真实+虚拟+NULL） int total_count = real_count + 1; char** merged = (char**)XCALLOC(MTYPE_TMP, (total_count + 1) * sizeof(char*)); // 复制真实路径补全项 for (i = 0; i < real_count; i++) { merged[i] = filename_matches[i]; } // 添加虚拟路径补全项 merged[real_count] = XSTRDUP(MTYPE_TMP, virtual_prefix); merged[real_count + 1] = NULL; // 释放原数组容器（不释放字符串内容） if (filename_matches) { XFREE(MTYPE_TMP, filename_matches); } filename_matches = merged; int max_len_tmp = 0; if (filename_matches && real_count > 0) { for (i = 0; filename_matches[i]; i++) { int len = strlen(filename_matches[i]); if (len > max_len_tmp) max_len_tmp = len; } printf("\n"); rl_display_match_list(filename_matches, real_count, max_len_tmp); for (i = 0; filename_matches[i]; i++) XFREE(MTYPE_TMP, filename_matches[i]); XFREE(MTYPE_TMP, filename_matches); return NULL; } } // ========== 虚拟路径前缀匹配处理结束 ========== if (!filename_matches || !filename_matches[0]) { return NULL; } // 处理单个匹配项（可能是目录或虚拟路径） if (filename_matches && filename_matches[1] == NULL) { const char* match = filename_matches[0]; int match_len = strlen(match); // 检查是否应该自动展开 int should_expand = 0; if (text_len > 0 && text[text_len - 1] == '/') { should_expand = 1; } // 如果是目录（以 / 结尾）或虚拟路径 if (match_len > 0 && (match[match_len - 1] == '/' || strncmp(match, virtual_prefix, virtual_prefix_len) == 0)) { // 只在输入以斜杠结尾时展开目录 if (should_expand) { char fullpath[PATH_MAX]; int is_virtual = 0; // 解析路径 resolve_virtual_path(match, fullpath, sizeof(fullpath), &is_virtual); // 确保路径以/结尾 int fullpath_len = strlen(fullpath); if (fullpath_len > 0 && fullpath[fullpath_len - 1] != '/') { if (fullpath_len < sizeof(fullpath) - 1) { strcat(fullpath, "/"); } } // 检查是否是目录 struct stat st; if (stat(fullpath, &st) == 0 && S_ISDIR(st.st_mode)) { int count = 0, max_len = 0; char** sub_matches = list_directory_entries(fullpath, &count, &max_len); if (sub_matches && count > 0) { // 创建相对路径的显示数组 char** display_list = (char**)XCALLOC(MTYPE_TMP, (count + 1) * sizeof(char*)); int display_max_len = 0; // 计算要去除的前缀长度 size_t prefix_len = strlen(fullpath); for (int i = 0; i < count; i++) { if (strncmp(sub_matches[i], fullpath, prefix_len) == 0) { // 去除前缀，只显示相对部分 const char* relative_part = sub_matches[i] + prefix_len; display_list[i] = XSTRDUP(MTYPE_TMP, relative_part); } else { display_list[i] = XSTRDUP(MTYPE_TMP, sub_matches[i]); } int len = strlen(display_list[i]); if (len > display_max_len) display_max_len = len; } rl_display_match_list_tmp(display_list, count, display_max_len); // 清理所有分配的内存 for (int i = 0; i < count; i++) { XFREE(MTYPE_TMP, display_list[i]); XFREE(MTYPE_TMP, sub_matches[i]); } XFREE(MTYPE_TMP, display_list); XFREE(MTYPE_TMP, sub_matches); return NULL; } } } } } return filename_matches; } return matches; } 可以在这里的rl_display_match_list_tmp显示函数前做处理，也就是说虽然filename_completion_function返回的是带完整路径的，然后rl_display_match_list_tmp显示前做处理，只显示后边的文件
08-30
因此，我们可以修改显示部分的代码，创建一个新的字符串数组，其中每个字符串都是原匹配项的文件名部分（即最后一个斜杠之后的部分），然后使用这个新数组进行显示。 但是，注意在 `cmlsh_completion` 函数中，有...
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