1 #include <u.h> 2 #include <libc.h> 3 #include <bio.h> 4 #include "String.h" 5 6 /* Append an input line to a String. 7 * 8 * Returns a pointer to the character string (or 0). 9 * Leading whitespace and newlines are removed. 10 * 11 * Empty lines and lines starting with '#' are ignored. 12 */ 13 extern char * s_getline(Biobuf * fp,String * to)14s_getline(Biobuf *fp, String *to) 15 { 16 int c; 17 int len=0; 18 19 s_terminate(to); 20 21 /* end of input */ 22 if ((c = Bgetc(fp)) < 0) 23 return 0; 24 25 /* take care of inconsequentials */ 26 for(;;) { 27 /* eat leading white */ 28 while(c==' ' || c=='\t' || c=='\n' || c=='\r') 29 c = Bgetc(fp); 30 31 if(c < 0) 32 return 0; 33 34 /* take care of comments */ 35 if(c == '#'){ 36 do { 37 c = Bgetc(fp); 38 if(c < 0) 39 return 0; 40 } while(c != '\n'); 41 continue; 42 } 43 44 /* if we got here, we've gotten something useful */ 45 break; 46 } 47 48 /* gather up a line */ 49 for(;;) { 50 len++; 51 switch(c) { 52 case -1: 53 s_terminate(to); 54 return len ? to->ptr-len : 0; 55 case '\\': 56 c = Bgetc(fp); 57 if (c != '\n') { 58 s_putc(to, '\\'); 59 s_putc(to, c); 60 } 61 break; 62 case '\n': 63 s_terminate(to); 64 return len ? to->ptr-len : 0; 65 default: 66 s_putc(to, c); 67 break; 68 } 69 c = Bgetc(fp); 70 } 71 } 72