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#include <config.h>
#include <sys/types.h>
#include <assert.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "wordexp.h"
#include "glob.h"
static int
is_valid_variable_char(char c, int pos)
{
if ( (pos && c >= '0' && c <= '9') ||
c == '_' ||
(c >= 'a' && c <= 'z') ||
(c >= 'A' && c <= 'Z'))
return 1;
return 0;
}
/*
* @brief replace all names of $NAME ${NAME}
* with the corresponding environment variable
* @ param in: the string to be checked
* @ return the expanded string or a copy of the existing string
* must be free() by the calling function
*/
static char *
expand_variables(const char *in)
{
char *var,*pos,*ret=strdup(in);
char *val,*str;
pos=ret;
while ((var=strchr(pos, '$'))) {
char *name,*begin=var+1;
int npos=0,bpos=0,slen,elen;
*var='\0';
if (var[1] == '{') {
begin++;
while (begin[npos]) {
bpos=npos;
if (begin[npos++] == '}')
break;
}
} else {
while (is_valid_variable_char(begin[npos],npos))
npos++;
bpos=npos;
}
name=strdup(begin);
name[bpos]='\0';
val=getenv(name);
free(name);
if (! val)
val="";
slen=strlen(ret)+strlen(val);
elen=strlen(begin+npos);
str=malloc(slen+elen+1);
strcpy(str,ret);
strcat(str,val);
strcat(str,begin+npos);
free(ret);
ret=str;
pos=ret+slen;
}
return ret;
}
/*
* @brief minimal realization of wordexp according to IEEE standard
* shall perform word expansion as described in the Shell
* expansion of ´$NAME´ or ´${NAME}´
* expansion of ´*´ and ´?´
* @param words: pointer to a string containing one or more words to be expanded
* but here only one word supported
*/
int
wordexp(const char *words, wordexp_t *we, int flags)
{
int i;
int error;
char *words_expanded;
glob_t pglob;
assert(we != NULL);
assert(words != NULL);
/* expansion of ´$NAME´ or ´${NAME}´ */
words_expanded=expand_variables(words);
/* expansion of ´*´, ´?´ */
error=glob(words_expanded, 0, NULL, &pglob);
if (!error)
{
/* copy the content of struct of glob into struct of wordexp */
we->we_wordc = pglob.gl_pathc;
we->we_offs = pglob.gl_offs;
we->we_wordv = malloc(we->we_wordc * sizeof(char*));
for (i=0; i<we->we_wordc; i++)
{
we->we_wordv[i] = strdup(pglob.gl_pathv[i]);
}
globfree(&pglob);
free(words_expanded);
}
else
{
we->we_wordc = 1;
we->we_wordv = malloc(sizeof(char*));
we->we_wordv[0] = words_expanded;
}
return error;
}
void wordfree(wordexp_t *we)
{
int i;
for (i=0; i < we->we_wordc; i++)
{
free (we->we_wordv[i]);
}
free (we->we_wordv);
we->we_wordc = 0;
}
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