diff options
Diffstat (limited to 'src/libString/s_getline.c')
-rw-r--r-- | src/libString/s_getline.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/src/libString/s_getline.c b/src/libString/s_getline.c new file mode 100644 index 00000000..e46dc125 --- /dev/null +++ b/src/libString/s_getline.c @@ -0,0 +1,72 @@ +#include <u.h> +#include <libc.h> +#include <bio.h> +#include "libString.h" + +/* Append an input line to a String. + * + * Returns a pointer to the character string (or 0). + * Leading whitespace and newlines are removed. + * + * Empty lines and lines starting with '#' are ignored. + */ +extern char * +s_getline(Biobuf *fp, String *to) +{ + int c; + int len=0; + + s_terminate(to); + + /* end of input */ + if ((c = Bgetc(fp)) < 0) + return 0; + + /* take care of inconsequentials */ + for(;;) { + /* eat leading white */ + while(c==' ' || c=='\t' || c=='\n' || c=='\r') + c = Bgetc(fp); + + if(c < 0) + return 0; + + /* take care of comments */ + if(c == '#'){ + do { + c = Bgetc(fp); + if(c < 0) + return 0; + } while(c != '\n'); + continue; + } + + /* if we got here, we've gotten something useful */ + break; + } + + /* gather up a line */ + for(;;) { + len++; + switch(c) { + case -1: + s_terminate(to); + return len ? to->ptr-len : 0; + case '\\': + c = Bgetc(fp); + if (c != '\n') { + s_putc(to, '\\'); + s_putc(to, c); + } + break; + case '\n': + s_terminate(to); + return len ? to->ptr-len : 0; + default: + s_putc(to, c); + break; + } + c = Bgetc(fp); + } + return 0; +} |