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/*
* Poor developer's strings.
* (c) 2002, Sean D. True, WebReply.Com, Inc.
* Use freely, under the Python license
* In short: use with or without attribution as you like, but
* no warranty of fitness, suitability, or anything else is given!
*
* ChangeLog:
* superfluous printable() function deleted - 2002/02/20 - Nelson Murilo
*/
#include <stdio.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <ctype.h>
#include <stdlib.h>
#ifdef __FreeBSD__
#include <string.h>
#endif
#ifdef __linux__
#include <string.h>
#endif
#define MAXFILESIZE (4*1024*1024)
/*
* Many options here. The current choice produces a little more output
* than gnu strings
*/
/*
* Try to get the filesize via stat, and get a buffer to match
* Naievely allocate a 4MB buffer if we can't
* Fails badly if it allocate a buffer big enough to load a file
*/
unsigned char *filebuf(FILE *pf, int *sz) {
struct stat buf;
unsigned char *cdata;
if (fstat(fileno(pf), &buf) < 0) {
perror("fstat");
exit (1);
}
*sz = buf.st_size;
if(*sz == 0) *sz = MAXFILESIZE;
if ((cdata = malloc(*sz+1)) == NULL) {
perror("malloc");
exit (1);
}
return cdata;
}
/*
* Find printable strings of 4 or more characters
* Always scans entire file (-a option of gnu strings)
*/
void strings(FILE *pf) {
static char printme[1024];
int sz;
unsigned char *cdata;
int nread;
size_t printmeindex;
cdata = filebuf(pf,&sz);
nread = fread(cdata, 1, sz, pf);
printmeindex = 0;
if (nread > 0) {
int i;
unsigned char c;
int isprintable;
int iseol;
for (i = 0; i < nread; i++) {
c = cdata[i];
isprintable = isprint(c);
iseol = 0;
if (c == 0 || c == '\n' || printmeindex >= sizeof(printme)-1) iseol = 1;
if (iseol || !isprintable) {
if (printmeindex > 3 && iseol) {
printme[printmeindex++] = 0;
printf("%s\n", printme);
printmeindex = 0;
}
}
else if (isprintable) {
printme[printmeindex++] = c;
}
}
}
if (printmeindex > 3) {
printme[printmeindex++] = 0;
printf("%s\n", printme);
}
free(cdata);
}
/*
* Silently accepts the -a option
*/
int main(int argc, char **argv)
{
if (argc > 1) {
int i;
for (i = 1; i < argc; i++) {
FILE *pf;
if (strcmp(argv[i], "-a") == 0) continue;
if ((pf = fopen(argv[i],"rb")) == NULL) {
perror("fopen");
return(1);
}
strings(pf);
}
}
else {
strings(stdin);
}
return(0);
}
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