You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
50 lines
1.2 KiB
C
50 lines
1.2 KiB
C
#include "fmt.h"
|
|
#include "textcode.h"
|
|
|
|
size_t fmt_yenc(char* dest,const char* src,size_t len) {
|
|
register const unsigned char* s=(const unsigned char*) src;
|
|
size_t written=0,i;
|
|
int linelen=0;
|
|
for (i=0; i<len; ++i) {
|
|
unsigned char c=s[i]+42;
|
|
switch (c) {
|
|
case ' ': /* escape space at line ending */
|
|
if (linelen==253) {
|
|
if (dest) dest[written]='\n';
|
|
++written; linelen=0;
|
|
}
|
|
goto dontescape;
|
|
case 'F': /* escape "^From " */
|
|
if (s[i+1]+42!='r' || s[i+2]+42!='o' || s[i+3]+42!='m' || s[i+4]+42!=' ') goto dontescape;
|
|
/* fall through */
|
|
case '.': /* dot at start of line needs to be escaped */
|
|
if (!linelen) goto dontescape;
|
|
/* fall through */
|
|
case 0:
|
|
case '\n':
|
|
case '\r':
|
|
case '=':
|
|
if (dest) dest[written]='=';
|
|
++written;
|
|
c+=64;
|
|
/* fall through */
|
|
default:
|
|
dontescape:
|
|
++linelen;
|
|
if (dest) dest[written]=c;
|
|
++written;
|
|
if (linelen>253) {
|
|
if (dest) dest[written]='\n';
|
|
++written; linelen=0;
|
|
}
|
|
}
|
|
/* in case someone gives us malicious input */
|
|
if (written>((size_t)-1)/2) return (size_t)-1;
|
|
}
|
|
if (linelen) {
|
|
if (dest) dest[written]='\n';
|
|
++written;
|
|
}
|
|
return written;
|
|
}
|