#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; 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; linelen=0; } return written; }