+
+/*
+ * vfmtmsg - format a message into a buffer. Like vsprintf except we
+ * also specify the length of the output buffer, and we handle the
+ * %m (error message) format.
+ * Doesn't do floating-point formats.
+ * Returns the number of chars put into buf.
+ */
+#define OUTCHAR(c) (buflen > 0? (--buflen, *buf++ = (c)): 0)
+
+int
+vfmtmsg(buf, buflen, fmt, args)
+ char *buf;
+ int buflen;
+ const char *fmt;
+ va_list args;
+{
+ int c, i, n;
+ int width, prec, fillch;
+ int base, len, neg, quoted;
+ unsigned long val = 0;
+ char *str, *buf0;
+ const char *f;
+ unsigned char *p;
+ char num[32];
+ time_t t;
+ static char hexchars[] = "0123456789abcdef";
+
+ buf0 = buf;
+ --buflen;
+ while (buflen > 0) {
+ for (f = fmt; *f != '%' && *f != 0; ++f)
+ ;
+ if (f > fmt) {
+ len = f - fmt;
+ if (len > buflen)
+ len = buflen;
+ memcpy(buf, fmt, len);
+ buf += len;
+ buflen -= len;
+ fmt = f;
+ }
+ if (*fmt == 0)
+ break;
+ c = *++fmt;
+ width = prec = 0;
+ fillch = ' ';
+ if (c == '0') {
+ fillch = '0';
+ c = *++fmt;
+ }
+ if (c == '*') {
+ width = va_arg(args, int);
+ c = *++fmt;
+ } else {
+ while (isdigit(c)) {
+ width = width * 10 + c - '0';
+ c = *++fmt;
+ }
+ }
+ if (c == '.') {
+ c = *++fmt;
+ if (c == '*') {
+ prec = va_arg(args, int);
+ c = *++fmt;
+ } else {
+ while (isdigit(c)) {
+ prec = prec * 10 + c - '0';
+ c = *++fmt;
+ }
+ }
+ }
+ str = 0;
+ base = 0;
+ neg = 0;
+ ++fmt;
+ switch (c) {
+ case 'd':
+ i = va_arg(args, int);
+ if (i < 0) {
+ neg = 1;
+ val = -i;
+ } else
+ val = i;
+ base = 10;
+ break;
+ case 'o':
+ val = va_arg(args, unsigned int);
+ base = 8;
+ break;
+ case 'x':
+ val = va_arg(args, unsigned int);
+ base = 16;
+ break;
+ case 'p':
+ val = (unsigned long) va_arg(args, void *);
+ base = 16;
+ neg = 2;
+ break;
+ case 's':
+ str = va_arg(args, char *);
+ break;
+ case 'c':
+ num[0] = va_arg(args, int);
+ num[1] = 0;
+ str = num;
+ break;
+ case 'm':
+ str = strerror(errno);
+ break;
+ case 'v': /* "visible" string */
+ case 'q': /* quoted string */
+ quoted = c == 'q';
+ p = va_arg(args, unsigned char *);
+ if (fillch == '0' && prec > 0) {
+ n = prec;
+ } else {
+ n = strlen((char *)p);
+ if (prec > 0 && prec < n)
+ n = prec;
+ }
+ while (n > 0 && buflen > 0) {
+ c = *p++;
+ --n;
+ if (!quoted && c >= 0x80) {
+ OUTCHAR('M');
+ OUTCHAR('-');
+ c -= 0x80;
+ }
+ if (quoted && (c == '"' || c == '\\'))
+ OUTCHAR('\\');
+ if (c < 0x20 || (0x7f <= c && c < 0xa0)) {
+ if (quoted) {
+ OUTCHAR('\\');
+ switch (c) {
+ case '\t': OUTCHAR('t'); break;
+ case '\n': OUTCHAR('n'); break;
+ case '\b': OUTCHAR('b'); break;
+ case '\f': OUTCHAR('f'); break;
+ default:
+ OUTCHAR('x');
+ OUTCHAR(hexchars[c >> 4]);
+ OUTCHAR(hexchars[c & 0xf]);
+ }
+ } else {
+ if (c == '\t')
+ OUTCHAR(c);
+ else {
+ OUTCHAR('^');
+ OUTCHAR(c ^ 0x40);
+ }
+ }
+ } else
+ OUTCHAR(c);
+ }
+ continue;
+ default:
+ *buf++ = '%';
+ if (c != '%')
+ --fmt; /* so %z outputs %z etc. */
+ --buflen;
+ continue;
+ }
+ if (base != 0) {
+ str = num + sizeof(num);
+ *--str = 0;
+ while (str > num + neg) {
+ *--str = hexchars[val % base];
+ val = val / base;
+ if (--prec <= 0 && val == 0)
+ break;
+ }
+ switch (neg) {
+ case 1:
+ *--str = '-';
+ break;
+ case 2:
+ *--str = 'x';
+ *--str = '0';
+ break;
+ }
+ len = num + sizeof(num) - 1 - str;
+ } else {
+ len = strlen(str);
+ if (prec > 0 && len > prec)
+ len = prec;
+ }
+ if (width > 0) {
+ if (width > buflen)
+ width = buflen;
+ if ((n = width - len) > 0) {
+ buflen -= n;
+ for (; n > 0; --n)
+ *buf++ = fillch;
+ }
+ }
+ if (len > buflen)
+ len = buflen;
+ memcpy(buf, str, len);
+ buf += len;
+ buflen -= len;
+ }
+ *buf = 0;
+ return buf - buf0;
+}
projects / ppp.git / commitdiff