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-rw-r--r--libc/stdio/printf.c618
1 files changed, 398 insertions, 220 deletions
diff --git a/libc/stdio/printf.c b/libc/stdio/printf.c
index d987966f6..634885e67 100644
--- a/libc/stdio/printf.c
+++ b/libc/stdio/printf.c
@@ -17,11 +17,92 @@
* -RDB
*/
+/*
+ * Manuel Novoa III Dec 2000
+ *
+ * The previous vfprintf routine was almost completely rewritten with the
+ * goal of fixing some shortcomings and reducing object size.
+ *
+ * The summary of changes:
+ *
+ * Converted print conversion specification parsing from one big switch
+ * to a method using string tables. This new method verifies that the
+ * conversion flags, field width, precision, qualifier, and specifier
+ * appear in the correct order. Many questionable specifications were
+ * accepted by the previous code. This new method also resulted in a
+ * substantial reduction in object size of about 330 bytes (20%) from
+ * the old version (1627 bytes) on i386, even with the following
+ * improvements.
+ *
+ * Implemented %n specifier as required by the standards.
+ * Implemented proper handling of precision for int types.
+ * Implemented # for hex and pointer, fixed error for octal rep of 0.
+ * Implemented return of -1 on stream error.
+ *
+ * Added optional support for the GNU extension %m which prints the string
+ * corresponding the errno.
+ *
+ * Added optional support for long long ints and unsigned long long ints
+ * using the conversion qualifiers "ll", "L", or "q" (like glibc).
+ *
+ * Added optional support for doubles in a very limited form. None of
+ * the formating options are obeyed. The string returned by __dtostr
+ * is printed directly.
+ *
+ * Converted to use my (un)signed long (long) to string routines, which are
+ * smaller than the previous functions and don't require static buffers.
+ *
+ */
+
+/*****************************************************************************/
+/* OPTIONS */
+/*****************************************************************************/
+/* The optional support for long longs and doubles comes in two forms.
+ *
+ * 1) Normal (or partial for doubles) output support. Set to 1 to turn on.
+ * Adds about 54 byes and about 217 bytes for long longss to the base size
+ * of 1298. (Bizarre: both turned on is smaller than WANT_LONG_LONG only.)
+ */
+
+#define WANT_LONG_LONG 0
+#define WANT_DOUBLE 0
+
+/* 2) An error message is inserted into the stream, an arg of the
+ * appropriate size is removed from the arglist, and processing
+ * continues. This is adds less code and may be useful in some
+ * cases. Set to 1 to turn on. Adds about 31 bytes for doubles
+ * and about 54 bytes for long longs to the base size of 1298.
+ */
+
+#define WANT_LONG_LONG_ERROR 0
+#define WANT_DOUBLE_ERROR 0
+
+/*
+ * Set to support GNU extension of %m to print string corresponding to errno.
+ *
+ * Warning: This adds about 50 bytes (i386) to the code but it also pulls in
+ * strerror and the corresponding string table which together are about 3.8k.
+ */
+
+#define WANT_GNU_ERRNO 0
+
+/*
+ * Use fputc instead of macro putc. Slower but saves about 36 bytes.
+ */
+
+#define WANT_FPUTC 0
+
+/**************************************************************************/
+
#include <sys/types.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
+#if WANT_GNU_ERRNO
+#include <errno.h>
+#endif
+
#ifdef __STDC__
#include <stdarg.h>
#define va_strt va_start
@@ -32,14 +113,16 @@
#include "stdio.h"
+#if WANT_FPUTC
+#undef putc
+#define putc(c,s) fputc(c,s)
+#endif
extern int vfnprintf(FILE * op, size_t max_size,
register __const char *fmt, register va_list ap);
-
-
#ifdef L_printf
int printf(const char *fmt, ...)
{
@@ -150,93 +233,64 @@ int vsnprintf(char *sp, size_t size, __const char *fmt, va_list ap)
#ifdef L_vfprintf
-#if FLOATS
-int _vfprintf_fp_ref = 1;
+extern char *__ultostr(char *buf, unsigned long uval, int base, int uppercase);
+extern char *__ltostr(char *buf, long val, int base, int uppercase);
+extern char *__ulltostr(char *buf, unsigned long long uval, int base, int uppercase);
+extern char *__lltostr(char *buf, long long val, int base, int uppercase);
+extern char *__dtostr(char *buf, double x);
+
+enum {
+ FLAG_PLUS = 0,
+ FLAG_MINUS_LJUSTIFY,
+ FLAG_HASH,
+ FLAG_0_PAD,
+ FLAG_SPACE,
+};
+
+/* layout 01234 */
+static const char spec[] = "+-#0 ";
+
+#if WANT_LONG_LONG || WANT_LONG_LONG_ERROR
+static const char qual[] = "hlLq";
#else
-int _vfprintf_fp_ref = 0;
+static const char qual[] = "hl";
#endif
-static int
-printfield(op, buf, ljustf, sign, pad, width, preci, buffer_mode, max_size,
- current_size)
-register FILE *op;
-register unsigned char *buf;
-int ljustf;
-register char sign;
-char pad;
-register int width;
-int preci;
-int buffer_mode;
-size_t max_size;
-size_t current_size;
-
-/*
- * Output the given field in the manner specified by the arguments. Return
- * the number of characters output.
- */
-{
- register int cnt = 0, len;
- register unsigned char ch;
-
- len = strlen(buf);
-
- if (*buf == '-')
- sign = *buf++;
- else if (sign)
- len++;
-
- if ((preci != -1) && (len > preci)) /* limit max data width */
- len = preci;
-
- if (width < len) /* flexible field width or width overflow */
- width = len;
-
- /*
- * at this point: width = total field width len = actual data width
- * (including possible sign character)
- */
- cnt = width;
- width -= len;
-
- while (width || len) {
- if (!ljustf && width) { /* left padding */
- if (len && sign && (pad == '0'))
- goto showsign;
- ch = pad;
- --width;
- } else if (len) {
- if (sign) {
- showsign:ch = sign;
- /* sign */
- sign = '\0';
- } else
- ch = *buf++; /* main field */
- --len;
- } else {
- ch = pad; /* right padding */
- --width;
- }
- current_size++;
- if (max_size > 0 && current_size < max_size)
- putc(ch, op);
- if (ch == '\n' && buffer_mode == _IOLBF)
- fflush(op);
- }
+#if !WANT_LONG_LONG && WANT_LONG_LONG_ERROR
+static const char ll_err[] = "<LONG-LONG>";
+#endif
- return (cnt);
-}
+#if !WANT_DOUBLE && WANT_DOUBLE_ERROR
+static const char dbl_err[] = "<DOUBLE>";
+#endif
+#if WANT_DOUBLE || WANT_DOUBLE_ERROR
+/* layout 012345678901234567 */
+static const char u_spec[] = "%nbopxXudicsfgGeEaA";
+#else
+/* layout 0123456789012 */
+static const char u_spec[] = "%nbopxXudics0";
+#endif
+/* WARNING: u_spec and u_radix need to stay in agreement!!! */
+/* u_radix[i] <-> u_spec[i+2] for unsigned entries only */
+static const char u_radix[] = "\x02\x08\x10\x10\x10\x0a";
-int vfnprintf(FILE * op, size_t max_size, register __const char *fmt,
- register va_list ap)
+int vfnprintf(FILE * op, size_t max_size, const char *fmt, va_list ap)
{
- register int i, cnt = 0, ljustf, lval;
- int preci, dpoint, width;
- char pad, sign, radix, hash;
- register char *ptmp;
- char tmp[64], *ltostr(), *ultostr();
+ int i, cnt = 0, lval;
+ char *p;
+ const char *fmt0;
int buffer_mode;
+ int preci, width;
+#define upcase i
+ int radix, dpoint /*, upcase*/;
+#if WANT_LONG_LONG
+ char tmp[65];
+#else
+ char tmp[33];
+#endif
+ char flag[sizeof(spec)];
/* This speeds things up a bit for unbuffered */
buffer_mode = (op->mode & __MODE_BUF);
@@ -244,172 +298,296 @@ int vfnprintf(FILE * op, size_t max_size, register __const char *fmt,
while (*fmt) {
if (*fmt == '%') {
- if (buffer_mode == _IONBF)
+ fmt0 = fmt; /* save our position in case of bad format */
+ ++fmt;
+ if (buffer_mode == _IONBF) {
fflush(op);
- ljustf = 0; /* left justify flag */
- sign = '\0'; /* sign char & status */
- pad = ' '; /* justification padding char */
+ }
width = -1; /* min field width */
- dpoint = 0; /* found decimal point */
- preci = -1; /* max data width */
+ preci = -5; /* max string width or mininum digits */
radix = 10; /* number base */
- ptmp = tmp; /* pointer to area to print */
- hash = 0;
+ dpoint = 0; /* found decimal point */
lval = (sizeof(int) == sizeof(long)); /* long value flaged */
- fmtnxt:
- i = 0;
- for (;;) {
- ++fmt;
- if (*fmt < '0' || *fmt > '9')
- break;
- i = (i * 10) + (*fmt - '0');
- if (dpoint)
- preci = i;
- else if (!i && (pad == ' ')) {
- pad = '0';
- goto fmtnxt;
- } else
- width = i;
- }
-
- switch (*fmt) {
- case '\0': /* early EOS */
- --fmt;
- goto charout;
+ tmp[1] = 0; /* set things up for %c -- better done here */
- case '-': /* left justification */
- ljustf = 1;
- goto fmtnxt;
+ /* init flags */
+ for (p =(char *) spec ; *p ; p++) {
+ flag[p-spec] = '\0';
+ }
+ flag[FLAG_0_PAD] = ' ';
- case ' ':
- case '+': /* leading sign flag */
- sign = *fmt;
- goto fmtnxt;
+ /* process optional flags */
+ for (p = (char *)spec ; *p ; p++) {
+ if (*fmt == *p) {
+ flag[p-spec] = *fmt++;
+ p = (char *)spec; /* restart scan */
+ }
+ }
+
+ if (!flag[FLAG_PLUS]) {
+ flag[FLAG_PLUS] = flag[FLAG_SPACE];
+ }
- case '*': /* parameter width value */
- i = va_arg(ap, int);
+ /* process optional width and precision */
+ do {
+ if (*fmt == '.') {
+ ++fmt;
+ dpoint = 1;
+ }
+ if (*fmt == '*') { /* parameter width value */
+ ++fmt;
+ i = va_arg(ap, int);
+ } else {
+ for ( i = 0 ; (*fmt >= '0') && (*fmt <= '9') ; ++fmt ) {
+ i = (i * 10) + (*fmt - '0');
+ }
+ }
- if (dpoint)
+ if (dpoint) {
preci = i;
- else
+ if (i<0) {
+ preci = 0;
+ }
+ } else {
width = i;
- goto fmtnxt;
-
- case '.': /* secondary width field */
- dpoint = 1;
- goto fmtnxt;
-
- case 'l': /* long data */
- lval = 1;
- goto fmtnxt;
+ if (i<0) {
+ width = -i;
+ flag[FLAG_MINUS_LJUSTIFY] = 1;
+ }
+ }
+ } while ((*fmt == '.') && !dpoint );
+
+ /* process optional qualifier */
+ for (p = (char *) qual ; *p ; p++) {
+ if (*p == *fmt) {
+ lval = p - qual;
+ ++fmt;
+#if WANT_LONG_LONG || WANT_LONG_LONG_ERROR
+ if ((*p == 'l') && (*fmt == *p)) {
+ ++lval;
+ ++fmt;
+ }
+#endif /* WANT_LONG_LONG || WANT_LONG_LONG_ERROR */
+ }
+ }
- case 'h': /* short data */
- lval = 0;
- goto fmtnxt;
+#if WANT_GNU_ERRNO
+ if (*fmt == 'm') {
+ flag[FLAG_PLUS] = '\0';
+ flag[FLAG_0_PAD] = ' ';
+ p = strerror(errno);
+ goto print;
+ }
+#endif
- case 'd': /* Signed decimal */
- case 'i':
- ptmp = ltostr((long) ((lval)
+ /* process format specifier */
+ for (p = (char *) u_spec ; *p ; p++) {
+ if (*fmt != *p) continue;
+ if (p-u_spec < 1) { /* print a % */
+ goto charout;
+ }
+ if (p-u_spec < 2) { /* store output count in int ptr */
+ *(va_arg(ap, int *)) = cnt;
+ goto nextfmt;
+ }
+ if (p-u_spec < 8) { /* unsigned conversion */
+ radix = u_radix[p-u_spec-2];
+ upcase = ((int)'x') - *p;
+ if (*p == 'p') {
+ lval = (sizeof(char *) == sizeof(long));
+ upcase = 0;
+ }
+#if WANT_LONG_LONG || WANT_LONG_LONG_ERROR
+ if (lval >= 2) {
+#if WANT_LONG_LONG
+ p = __ulltostr(tmp + sizeof(tmp) - 1,
+ va_arg(ap, unsigned long long),
+ radix, upcase);
+#else
+ (void) va_arg(ap, unsigned long long); /* cary on */
+ p = (char *) ll_err;
+#endif /* WANT_LONG_LONG */
+ } else {
+#endif /* WANT_LONG_LONG || WANT_LONG_LONG_ERROR */
+ p = __ultostr(tmp + sizeof(tmp) - 1, (unsigned long)
+ ((lval)
+ ? va_arg(ap, unsigned long)
+ : va_arg(ap, unsigned short)),
+ radix, upcase);
+#if WANT_LONG_LONG || WANT_LONG_LONG_ERROR
+ }
+#endif /* WANT_LONG_LONG || WANT_LONG_LONG_ERROR */
+ flag[FLAG_PLUS] = '\0'; /* meaningless for unsigned */
+ if (flag[FLAG_HASH]) {
+ switch (radix) {
+ case 16:
+ flag[FLAG_PLUS] = '0';
+ *--p = 'x';
+ if (*fmt == 'X') {
+ *p = 'X';
+ }
+ break;
+ case 8:
+ if (*p != '0') { /* if not zero */
+ *--p = '0'; /* add leadding zero */
+ }
+ }
+ }
+ } else if (p-u_spec < 10) { /* signed conversion */
+#if WANT_LONG_LONG || WANT_LONG_LONG_ERROR
+ if (lval >= 2) {
+#if WANT_LONG_LONG
+ p = __lltostr(tmp + sizeof(tmp) - 1,
+ va_arg(ap, long long), 10, 0);
+#else
+ (void) va_arg(ap, long long); /* carry on */
+ p = (char *) ll_err;
+#endif /* WANT_LONG_LONG */
+ } else {
+#endif /* WANT_LONG_LONG || WANT_LONG_LONG_ERROR */
+ p = __ltostr(tmp + sizeof(tmp) - 1, (long)
+ ((lval)
? va_arg(ap, long)
: va_arg(ap, short)), 10, 0);
+#if WANT_LONG_LONG || WANT_LONG_LONG_ERROR
+ }
+#endif /* WANT_LONG_LONG || WANT_LONG_LONG_ERROR */
+ } else if (p-u_spec < 12) { /* character or string */
+ flag[FLAG_PLUS] = '\0';
+ flag[FLAG_0_PAD] = ' ';
+ if (*p == 'c') { /* character */
+ p = tmp;
+ *p = va_arg(ap, int);
+ } else { /* string */
+ p = va_arg(ap, char *);
+ }
+#if WANT_DOUBLE || WANT_DOUBLE_ERROR
+ } else if (p-u_spec < 27) { /* floating point */
+#endif /* WANT_DOUBLE || WANT_DOUBLE_ERROR */
+#if WANT_DOUBLE
+ p = __dtostr(tmp + sizeof(tmp) - 1, va_arg(ap, double));
+#elif WANT_DOUBLE_ERROR
+ (void) va_arg(ap,double); /* carry on */
+ p = (char *) dbl_err;
+#endif /* WANT_DOUBLE */
+ }
- goto printit;
-
- case 'b': /* Unsigned binary */
- radix = 2;
- goto usproc;
-
- case 'o': /* Unsigned octal */
- radix = 8;
- goto usproc;
-
- case 'p': /* Pointer */
- lval = (sizeof(char *) == sizeof(long));
-
- pad = '0';
- width = 6;
- preci = 8;
- /* fall thru */
-
- case 'x': /* Unsigned hexadecimal */
- case 'X':
- radix = 16;
- /* fall thru */
+#if WANT_GNU_ERRNO
+ print:
+#endif
+ { /* this used to be printfield */
+ int len;
- case 'u': /* Unsigned decimal */
- usproc:
- ptmp = ultostr((unsigned long) ((lval)
- ? va_arg(ap, unsigned long)
- : va_arg(ap,
- unsigned short)),
- radix, (*fmt == 'X') ? 1 : 0);
+ /* cheaper than strlen call */
+ for ( len = 0 ; p[len] ; len++ ) { }
- if (hash && radix == 8) {
- width = strlen(ptmp) + 1;
- pad = '0';
- }
- goto printit;
-
- case '#':
- hash = 1;
- goto fmtnxt;
-
- case 'c': /* Character */
- ptmp[0] = va_arg(ap, int);
-
- ptmp[1] = '\0';
- goto nopad;
-
- case 's': /* String */
- ptmp = va_arg(ap, char *);
-
- nopad:
- sign = '\0';
- pad = ' ';
- printit:
- cnt += printfield(op, ptmp, ljustf, sign, pad, width,
- preci, buffer_mode, max_size, cnt);
- break;
-
-#if FLOATS
- case 'e': /* float */
- case 'f':
- case 'g':
- case 'E':
- case 'G':
- fprintf(stderr, "LIBM:PRINTF");
- gcvt(va_arg(ap, double), preci, ptmp);
-
- preci = -1;
- goto printit;
-#else
- case 'e': /* float */
- case 'f':
- case 'g':
- case 'E':
- case 'G':
- fprintf(stderr, "LIBC:PRINTF");
- exit(-1);
+ if ((*p == '-')
+#if WANT_GNU_ERRNO
+ && (*fmt != 'm')
#endif
-
- default: /* unknown character */
- goto charout;
+ && (*fmt != 's')) {
+ flag[FLAG_PLUS] = *p++;
+ --len;
+ }
+ if (flag[FLAG_PLUS]) {
+ ++len;
+ ++preci;
+ if (flag[FLAG_PLUS] == '0') { /* base 16 */
+ ++preci; /* account for x or X */
+ }
+ }
+
+ if (preci >= 0) {
+ if ((*fmt == 's')
+#if WANT_GNU_ERRNO
+ || (*fmt == 'm')
+#endif
+ ) {
+ len = preci;
+ }
+ preci -= len;
+ if (preci < 0) {
+ preci = 0;
+ }
+ width -= preci;
+ }
+
+ width -= len;
+ if (width < 0) {
+ width = 0;
+ }
+
+ if (preci < 0) {
+ preci = 0;
+ if (flag[FLAG_PLUS]
+ && !flag[FLAG_MINUS_LJUSTIFY]
+ && (flag[FLAG_0_PAD] == '0')) {
+ preci = width;
+ width = 0;
+ }
+ }
+
+ while (width + len + preci) {
+ unsigned char ch;
+ /* right padding || left padding */
+ if ((!len && !preci)
+ || (width && !flag[FLAG_MINUS_LJUSTIFY])) {
+ ch = ' ';
+ --width;
+ } else if (flag[FLAG_PLUS]) {
+ ch = flag[FLAG_PLUS]; /* sign */
+ if (flag[FLAG_PLUS]=='0') { /* base 16 case */
+ flag[FLAG_PLUS] = *p++; /* get the x|X */
+ } else {
+ flag[FLAG_PLUS] = '\0';
+ }
+ --len;
+ } else if (preci) {
+ ch = '0';
+ --preci;
+ } else {
+ ch = *p++; /* main field */
+ --len;
+ }
+
+ if (++cnt < max_size) {
+ putc(ch, op);
+ }
+ if ((ch == '\n') && (buffer_mode == _IOLBF)) {
+ fflush(op);
+ }
+ }
+ }
+ goto nextfmt;
}
- } else {
- charout:
- if (max_size > 0 && ++cnt < max_size)
- putc(*fmt, op); /* normal char out */
- if (*fmt == '\n' && buffer_mode == _IOLBF)
- fflush(op);
+
+ fmt = fmt0; /* this was an illegal format */
+ }
+
+ charout:
+ if (++cnt < max_size) {
+ putc(*fmt, op); /* normal char out */
+ }
+ if ((*fmt == '\n') && (buffer_mode == _IOLBF)) {
+ fflush(op);
}
+
+ nextfmt:
++fmt;
}
+
op->mode |= buffer_mode;
- if (buffer_mode == _IONBF)
+ if (buffer_mode == _IONBF) {
fflush(op);
- if (buffer_mode == _IOLBF)
+ }
+ if (buffer_mode == _IOLBF) {
op->bufwrite = op->bufstart;
+ }
+
+ if (ferror(op)) {
+ cnt = -1;
+ }
return (cnt);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-02 09:05:39 +0000