diff options
Diffstat (limited to 'contrib/nvi/vi/getc.c')
| -rw-r--r-- | contrib/nvi/vi/getc.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/contrib/nvi/vi/getc.c b/contrib/nvi/vi/getc.c new file mode 100644 index 0000000..5e60ade --- /dev/null +++ b/contrib/nvi/vi/getc.c @@ -0,0 +1,234 @@ +/*- + * Copyright (c) 1992, 1993, 1994 + * The Regents of the University of California. All rights reserved. + * Copyright (c) 1992, 1993, 1994, 1995, 1996 + * Keith Bostic. All rights reserved. + * + * See the LICENSE file for redistribution information. + */ + +#include "config.h" + +#ifndef lint +static const char sccsid[] = "@(#)getc.c 10.10 (Berkeley) 3/6/96"; +#endif /* not lint */ + +#include <sys/types.h> +#include <sys/queue.h> +#include <sys/time.h> + +#include <bitstring.h> +#include <ctype.h> +#include <limits.h> +#include <stdio.h> +#include <stdlib.h> + +#include "../common/common.h" +#include "vi.h" + +/* + * Character stream routines -- + * These routines return the file a character at a time. There are two + * special cases. First, the end of a line, end of a file, start of a + * file and empty lines are returned as special cases, and no character + * is returned. Second, empty lines include lines that have only white + * space in them, because the vi search functions don't care about white + * space, and this makes it easier for them to be consistent. + */ + +/* + * cs_init -- + * Initialize character stream routines. + * + * PUBLIC: int cs_init __P((SCR *, VCS *)); + */ +int +cs_init(sp, csp) + SCR *sp; + VCS *csp; +{ + int isempty; + + if (db_eget(sp, csp->cs_lno, &csp->cs_bp, &csp->cs_len, &isempty)) { + if (isempty) + msgq(sp, M_BERR, "177|Empty file"); + return (1); + } + if (csp->cs_len == 0 || v_isempty(csp->cs_bp, csp->cs_len)) { + csp->cs_cno = 0; + csp->cs_flags = CS_EMP; + } else { + csp->cs_flags = 0; + csp->cs_ch = csp->cs_bp[csp->cs_cno]; + } + return (0); +} + +/* + * cs_next -- + * Retrieve the next character. + * + * PUBLIC: int cs_next __P((SCR *, VCS *)); + */ +int +cs_next(sp, csp) + SCR *sp; + VCS *csp; +{ + char *p; + + switch (csp->cs_flags) { + case CS_EMP: /* EMP; get next line. */ + case CS_EOL: /* EOL; get next line. */ + if (db_get(sp, ++csp->cs_lno, 0, &p, &csp->cs_len)) { + --csp->cs_lno; + csp->cs_flags = CS_EOF; + } else { + csp->cs_bp = p; + if (csp->cs_len == 0 || + v_isempty(csp->cs_bp, csp->cs_len)) { + csp->cs_cno = 0; + csp->cs_flags = CS_EMP; + } else { + csp->cs_flags = 0; + csp->cs_ch = csp->cs_bp[csp->cs_cno = 0]; + } + } + break; + case 0: + if (csp->cs_cno == csp->cs_len - 1) + csp->cs_flags = CS_EOL; + else + csp->cs_ch = csp->cs_bp[++csp->cs_cno]; + break; + case CS_EOF: /* EOF. */ + break; + default: + abort(); + /* NOTREACHED */ + } + return (0); +} + +/* + * cs_fspace -- + * If on a space, eat forward until something other than a + * whitespace character. + * + * XXX + * Semantics of checking the current character were coded for the fword() + * function -- once the other word routines are converted, they may have + * to change. + * + * PUBLIC: int cs_fspace __P((SCR *, VCS *)); + */ +int +cs_fspace(sp, csp) + SCR *sp; + VCS *csp; +{ + if (csp->cs_flags != 0 || !isblank(csp->cs_ch)) + return (0); + for (;;) { + if (cs_next(sp, csp)) + return (1); + if (csp->cs_flags != 0 || !isblank(csp->cs_ch)) + break; + } + return (0); +} + +/* + * cs_fblank -- + * Eat forward to the next non-whitespace character. + * + * PUBLIC: int cs_fblank __P((SCR *, VCS *)); + */ +int +cs_fblank(sp, csp) + SCR *sp; + VCS *csp; +{ + for (;;) { + if (cs_next(sp, csp)) + return (1); + if (csp->cs_flags == CS_EOL || csp->cs_flags == CS_EMP || + csp->cs_flags == 0 && isblank(csp->cs_ch)) + continue; + break; + } + return (0); +} + +/* + * cs_prev -- + * Retrieve the previous character. + * + * PUBLIC: int cs_prev __P((SCR *, VCS *)); + */ +int +cs_prev(sp, csp) + SCR *sp; + VCS *csp; +{ + switch (csp->cs_flags) { + case CS_EMP: /* EMP; get previous line. */ + case CS_EOL: /* EOL; get previous line. */ + if (csp->cs_lno == 1) { /* SOF. */ + csp->cs_flags = CS_SOF; + break; + } + if (db_get(sp, /* The line should exist. */ + --csp->cs_lno, DBG_FATAL, &csp->cs_bp, &csp->cs_len)) { + ++csp->cs_lno; + return (1); + } + if (csp->cs_len == 0 || v_isempty(csp->cs_bp, csp->cs_len)) { + csp->cs_cno = 0; + csp->cs_flags = CS_EMP; + } else { + csp->cs_flags = 0; + csp->cs_cno = csp->cs_len - 1; + csp->cs_ch = csp->cs_bp[csp->cs_cno]; + } + break; + case CS_EOF: /* EOF: get previous char. */ + case 0: + if (csp->cs_cno == 0) + if (csp->cs_lno == 1) + csp->cs_flags = CS_SOF; + else + csp->cs_flags = CS_EOL; + else + csp->cs_ch = csp->cs_bp[--csp->cs_cno]; + break; + case CS_SOF: /* SOF. */ + break; + default: + abort(); + /* NOTREACHED */ + } + return (0); +} + +/* + * cs_bblank -- + * Eat backward to the next non-whitespace character. + * + * PUBLIC: int cs_bblank __P((SCR *, VCS *)); + */ +int +cs_bblank(sp, csp) + SCR *sp; + VCS *csp; +{ + for (;;) { + if (cs_prev(sp, csp)) + return (1); + if (csp->cs_flags == CS_EOL || csp->cs_flags == CS_EMP || + csp->cs_flags == 0 && isblank(csp->cs_ch)) + continue; + break; + } + return (0); +} |
