/**
* b u _ v l s _ v p r i n t f
*
* Format a string into a vls. This version should work on
* practically any machine, but it serves to highlight the the
* grossness of the varargs package requiring the size of a parameter
* to be known at compile time.
*
* %s continues to be a regular 'C' string, null terminated.
* %S is a pointer to a (struct bu_vls *) string.
*
* This routine appends to the given vls similar to how vprintf
* appends to stdout (see bu_vls_vsprintf for overwriting the vls).
*/
void
bu_vls_vprintf(struct bu_vls *vls, const char *fmt, va_list ap)
{
register const char *sp; /* start pointer */
register const char *ep; /* end pointer */
register int len;
#define LONGINT 0x001
#define FIELDLEN 0x002
#define SHORTINT 0x003
int flags;
int fieldlen=-1;
char fbuf[64] = {0}; /* % format buffer */
char buf[BUFSIZ] = {0};
if (!vls || !fmt || fmt[0] == '\0') {
/* nothing to print to or from */
return;
}
BU_CK_VLS(vls);
bu_vls_extend(vls, _VLS_ALLOC_STEP);
sp = fmt;
while ( *sp ) {
/* Initial state: just printing chars */
fmt = sp;
while (*sp != '%' && *sp)
sp++;
if (sp != fmt)
bu_vls_strncat(vls, fmt, (size_t)(sp-fmt));
if (*sp == '\0')
break;
/* Saw a percent sign, find end of fmt specifier */
flags = 0;
ep = sp;
while ( *ep ) {
++ep;
if (*ep == ' ' || *ep == '#' || *ep == '-' ||
*ep == '+' || *ep == '.' || isdigit(*ep))
continue;
else if (*ep == 'l' || *ep == 'U' || *ep == 'O')
flags |= LONGINT;
else if (*ep == '*') {
fieldlen = va_arg(ap, int);
flags |= FIELDLEN;
} else if (*ep == 'h') {
flags |= SHORTINT;
} else
/* Anything else must be the end of the fmt specifier */
break;
}
/*
The bu_vls_vprintf function aims to adhere to the following
specifications:
1. First, follow the POSIX man page at
"http://www.unix.com/man-page/POSIX/3/printf/" regarding the
definition of a format specifier.
2. Then modify [1] to accommodate a compatible subset of parts
applicable to a wide range of standard C libraries including
GNU/Linux, Windows, FreeBSD, and others as differences are
brought to our attention.
3. The subset [2] shall be the "valid" flags, length modifiers, and
conversion specifiers ("parts") accepted by this function.
Those are defined in the following local function:
format_part_status
4. Parts known to be defined outside subset [3] shall generate a
message stating such invalidity and giving a suitable
alternative if possible (such parts will be called "obsolete");
otherwise, the part shall be said to be "unsupported."
5. Parts seen by this function but not defined above shall be
deemed "unknown" and result in a suitable message.
6. Library users of this function receiving "unknown" messages
while attempting to use valid parts according to their O/S and
compiler need to contact the BRL-CAD developers to resolve the
issue. Resolution should normally result in assigning the
"unknown" part to one of the categories described in [4].
*/
void
bu_vls_vprintf(struct bu_vls *vls, const char *fmt, va_list ap)
{
const char *sp; /* start pointer */
const char *ep; /* end pointer */
int len;
/* flag variables are reset for each fmt specifier */
vflags_t f;
char buf[BUFSIZ] = {0};
int c;
struct bu_vls fbuf = BU_VLS_INIT_ZERO; /* % format buffer */
char *fbufp = NULL;
if (UNLIKELY(!vls || !fmt || fmt[0] == '\0')) {
/* nothing to print to or from */
return;
}
BU_CK_VLS(vls);
bu_vls_extend(vls, (unsigned int)_VLS_ALLOC_STEP);
sp = fmt;
while (*sp) {
/* Initial state: just printing chars */
fmt = sp;
while (*sp != '%' && *sp)
sp++;
if (sp != fmt)
bu_vls_strncat(vls, fmt, (size_t)(sp - fmt));
if (*sp == '\0')
break;
/* Saw a percent sign, now need to find end of fmt specifier */
/* All flags get reset for this fmt specifier */
reset_vflags(&f);
ep = sp;
while ((c = *(++ep))) {
if (c == ' '
|| c == '#'
|| c == '+'
|| c == '\''
)
{
/* skip */
} else if (c == '.') {
f.have_dot = 1;
} else if (isdigit(c)) {
/* skip */
} else if (c == '-') {
/* the first occurrence before a dot is the
left-justify flag, but the occurrence AFTER a dot is
taken to be zero precision */
if (f.have_dot) {
f.precision = 0;
f.have_digit = 0;
} else if (f.have_digit) {
/* FIXME: ERROR condition?: invalid format string
(e.g., '%7.8-f') */
/* seems as if the fprintf man page is indefinite here,
looks like the '-' is passed through and
appears in output */
;
} else {
f.left_justify = 1;
}
} else if (c == '*') {
/* the first occurrence is the field width, but the
second occurrence is the precision specifier */
if (!f.have_dot) {
f.fieldlen = va_arg(ap, int);
f.flags |= FIELDLEN;
} else {
f.precision = va_arg(ap, int);
f.flags |= PRECISION;
}
/* all length modifiers below here */
} else if (format_part_status(c) == (VP_VALID | VP_LENGTH_MOD)) {
