1 files changed, 606 insertions, 0 deletions

diff --git a/src/lj_strfmt.c b/src/lj_strfmt.c
new file mode 100644
index 00000000..5c808290
--- /dev/null
+++ b/src/lj_strfmt.c
@@ -0,0 +1,606 @@
+/*
+** String formatting.
+** Copyright (C) 2005-2022 Mike Pall. See Copyright Notice in luajit.h
+*/
+
+#include <stdio.h>
+
+#define lj_strfmt_c
+#define LUA_CORE
+
+#include "lj_obj.h"
+#include "lj_err.h"
+#include "lj_buf.h"
+#include "lj_str.h"
+#include "lj_meta.h"
+#include "lj_state.h"
+#include "lj_char.h"
+#include "lj_strfmt.h"
+#if LJ_HASFFI
+#include "lj_ctype.h"
+#endif
+#include "lj_lib.h"
+
+/* -- Format parser ------------------------------------------------------- */
+
+static const uint8_t strfmt_map[('x'-'A')+1] = {
+  STRFMT_A,0,0,0,STRFMT_E,STRFMT_F,STRFMT_G,0,0,0,0,0,0,
+  0,0,0,0,0,0,0,0,0,0,STRFMT_X,0,0,
+  0,0,0,0,0,0,
+  STRFMT_A,0,STRFMT_C,STRFMT_D,STRFMT_E,STRFMT_F,STRFMT_G,0,STRFMT_I,0,0,0,0,
+  0,STRFMT_O,STRFMT_P,STRFMT_Q,0,STRFMT_S,0,STRFMT_U,0,0,STRFMT_X
+};
+
+SFormat LJ_FASTCALL lj_strfmt_parse(FormatState *fs)
+{
+  const uint8_t *p = fs->p, *e = fs->e;
+  fs->str = (const char *)p;
+  for (; p < e; p++) {
+    if (*p == '%') {  /* Escape char? */
+      if (p[1] == '%') {  /* '%%'? */
+        fs->p = ++p+1;
+        goto retlit;
+      } else {
+        SFormat sf = 0;
+        uint32_t c;
+        if (p != (const uint8_t *)fs->str)
+          break;
+        for (p++; (uint32_t)*p - ' ' <= (uint32_t)('0' - ' '); p++) {
+          /* Parse flags. */
+          if (*p == '-') sf |= STRFMT_F_LEFT;
+          else if (*p == '+') sf |= STRFMT_F_PLUS;
+          else if (*p == '0') sf |= STRFMT_F_ZERO;
+          else if (*p == ' ') sf |= STRFMT_F_SPACE;
+          else if (*p == '#') sf |= STRFMT_F_ALT;
+          else break;
+        }
+        if ((uint32_t)*p - '0' < 10) {  /* Parse width. */
+          uint32_t width = (uint32_t)*p++ - '0';
+          if ((uint32_t)*p - '0' < 10)
+            width = (uint32_t)*p++ - '0' + width*10;
+          sf |= (width << STRFMT_SH_WIDTH);
+        }
+        if (*p == '.') {  /* Parse precision. */
+          uint32_t prec = 0;
+          p++;
+          if ((uint32_t)*p - '0' < 10) {
+            prec = (uint32_t)*p++ - '0';
+            if ((uint32_t)*p - '0' < 10)
+              prec = (uint32_t)*p++ - '0' + prec*10;
+          }
+          sf |= ((prec+1) << STRFMT_SH_PREC);
+        }
+        /* Parse conversion. */
+        c = (uint32_t)*p - 'A';
+        if (LJ_LIKELY(c <= (uint32_t)('x' - 'A'))) {
+          uint32_t sx = strfmt_map[c];
+          if (sx) {
+            fs->p = p+1;
+            return (sf | sx | ((c & 0x20) ? 0 : STRFMT_F_UPPER));
+          }
+        }
+        /* Return error location. */
+        if (*p >= 32) p++;
+        fs->len = (MSize)(p - (const uint8_t *)fs->str);
+        fs->p = fs->e;
+        return STRFMT_ERR;
+      }
+    }
+  }
+  fs->p = p;
+retlit:
+  fs->len = (MSize)(p - (const uint8_t *)fs->str);
+  return fs->len ? STRFMT_LIT : STRFMT_EOF;
+}
+
+/* -- Raw conversions ----------------------------------------------------- */
+
+#define WINT_R(x, sh, sc) \
+  { uint32_t d = (x*(((1<<sh)+sc-1)/sc))>>sh; x -= d*sc; *p++ = (char)('0'+d); }
+
+/* Write integer to buffer. */
+char * LJ_FASTCALL lj_strfmt_wint(char *p, int32_t k)
+{
+  uint32_t u = (uint32_t)k;
+  if (k < 0) { u = (uint32_t)-k; *p++ = '-'; }
+  if (u < 10000) {
+    if (u < 10) goto dig1;
+    if (u < 100) goto dig2;
+    if (u < 1000) goto dig3;
+  } else {
+    uint32_t v = u / 10000; u -= v * 10000;
+    if (v < 10000) {
+      if (v < 10) goto dig5;
+      if (v < 100) goto dig6;
+      if (v < 1000) goto dig7;
+    } else {
+      uint32_t w = v / 10000; v -= w * 10000;
+      if (w >= 10) WINT_R(w, 10, 10)
+      *p++ = (char)('0'+w);
+    }
+    WINT_R(v, 23, 1000)
+    dig7: WINT_R(v, 12, 100)
+    dig6: WINT_R(v, 10, 10)
+    dig5: *p++ = (char)('0'+v);
+  }
+  WINT_R(u, 23, 1000)
+  dig3: WINT_R(u, 12, 100)
+  dig2: WINT_R(u, 10, 10)
+  dig1: *p++ = (char)('0'+u);
+  return p;
+}
+#undef WINT_R
+
+/* Write pointer to buffer. */
+char * LJ_FASTCALL lj_strfmt_wptr(char *p, const void *v)
+{
+  ptrdiff_t x = (ptrdiff_t)v;
+  MSize i, n = STRFMT_MAXBUF_PTR;
+  if (x == 0) {
+    *p++ = 'N'; *p++ = 'U'; *p++ = 'L'; *p++ = 'L';
+    return p;
+  }
+#if LJ_64
+  /* Shorten output for 64 bit pointers. */
+  n = 2+2*4+((x >> 32) ? 2+2*(lj_fls((uint32_t)(x >> 32))>>3) : 0);
+#endif
+  p[0] = '0';
+  p[1] = 'x';
+  for (i = n-1; i >= 2; i--, x >>= 4)
+    p[i] = "0123456789abcdef"[(x & 15)];
+  return p+n;
+}
+
+/* Write ULEB128 to buffer. */
+char * LJ_FASTCALL lj_strfmt_wuleb128(char *p, uint32_t v)
+{
+  for (; v >= 0x80; v >>= 7)
+    *p++ = (char)((v & 0x7f) | 0x80);
+  *p++ = (char)v;
+  return p;
+}
+
+/* Return string or write number to tmp buffer and return pointer to start. */
+const char *lj_strfmt_wstrnum(lua_State *L, cTValue *o, MSize *lenp)
+{
+  SBuf *sb;
+  if (tvisstr(o)) {
+    *lenp = strV(o)->len;
+    return strVdata(o);
+  } else if (tvisbuf(o)) {
+    SBufExt *sbx = bufV(o);
+    *lenp = sbufxlen(sbx);
+    return sbx->r;
+  } else if (tvisint(o)) {
+    sb = lj_strfmt_putint(lj_buf_tmp_(L), intV(o));
+  } else if (tvisnum(o)) {
+    sb = lj_strfmt_putfnum(lj_buf_tmp_(L), STRFMT_G14, o->n);
+  } else {
+    return NULL;
+  }
+  *lenp = sbuflen(sb);
+  return sb->b;
+}
+
+/* -- Unformatted conversions to buffer ----------------------------------- */
+
+/* Add integer to buffer. */
+SBuf * LJ_FASTCALL lj_strfmt_putint(SBuf *sb, int32_t k)
+{
+  sb->w = lj_strfmt_wint(lj_buf_more(sb, STRFMT_MAXBUF_INT), k);
+  return sb;
+}
+
+#if LJ_HASJIT
+/* Add number to buffer. */
+SBuf * LJ_FASTCALL lj_strfmt_putnum(SBuf *sb, cTValue *o)
+{
+  return lj_strfmt_putfnum(sb, STRFMT_G14, o->n);
+}
+#endif
+
+SBuf * LJ_FASTCALL lj_strfmt_putptr(SBuf *sb, const void *v)
+{
+  sb->w = lj_strfmt_wptr(lj_buf_more(sb, STRFMT_MAXBUF_PTR), v);
+  return sb;
+}
+
+/* Add quoted string to buffer. */
+static SBuf *strfmt_putquotedlen(SBuf *sb, const char *s, MSize len)
+{
+  lj_buf_putb(sb, '"');
+  while (len--) {
+    uint32_t c = (uint32_t)(uint8_t)*s++;
+    char *w = lj_buf_more(sb, 4);
+    if (c == '"' || c == '\\' || c == '\n') {
+      *w++ = '\\';
+    } else if (lj_char_iscntrl(c)) {  /* This can only be 0-31 or 127. */
+      uint32_t d;
+      *w++ = '\\';
+      if (c >= 100 || lj_char_isdigit((uint8_t)*s)) {
+        *w++ = (char)('0'+(c >= 100)); if (c >= 100) c -= 100;
+        goto tens;
+      } else if (c >= 10) {
+      tens:
+        d = (c * 205) >> 11; c -= d * 10; *w++ = (char)('0'+d);
+      }
+      c += '0';
+    }
+    *w++ = (char)c;
+    sb->w = w;
+  }
+  lj_buf_putb(sb, '"');
+  return sb;
+}
+
+#if LJ_HASJIT
+SBuf * LJ_FASTCALL lj_strfmt_putquoted(SBuf *sb, GCstr *str)
+{
+  return strfmt_putquotedlen(sb, strdata(str), str->len);
+}
+#endif
+
+/* -- Formatted conversions to buffer ------------------------------------- */
+
+/* Add formatted char to buffer. */
+SBuf *lj_strfmt_putfchar(SBuf *sb, SFormat sf, int32_t c)
+{
+  MSize width = STRFMT_WIDTH(sf);
+  char *w = lj_buf_more(sb, width > 1 ? width : 1);
+  if ((sf & STRFMT_F_LEFT)) *w++ = (char)c;
+  while (width-- > 1) *w++ = ' ';
+  if (!(sf & STRFMT_F_LEFT)) *w++ = (char)c;
+  sb->w = w;
+  return sb;
+}
+
+/* Add formatted string to buffer. */
+static SBuf *strfmt_putfstrlen(SBuf *sb, SFormat sf, const char *s, MSize len)
+{
+  MSize width = STRFMT_WIDTH(sf);
+  char *w;
+  if (len > STRFMT_PREC(sf)) len = STRFMT_PREC(sf);
+  w = lj_buf_more(sb, width > len ? width : len);
+  if ((sf & STRFMT_F_LEFT)) w = lj_buf_wmem(w, s, len);
+  while (width-- > len) *w++ = ' ';
+  if (!(sf & STRFMT_F_LEFT)) w = lj_buf_wmem(w, s, len);
+  sb->w = w;
+  return sb;
+}
+
+#if LJ_HASJIT
+SBuf *lj_strfmt_putfstr(SBuf *sb, SFormat sf, GCstr *str)
+{
+  return strfmt_putfstrlen(sb, sf, strdata(str), str->len);
+}
+#endif
+
+/* Add formatted signed/unsigned integer to buffer. */
+SBuf *lj_strfmt_putfxint(SBuf *sb, SFormat sf, uint64_t k)
+{
+  char buf[STRFMT_MAXBUF_XINT], *q = buf + sizeof(buf), *w;
+#ifdef LUA_USE_ASSERT
+  char *ws;
+#endif
+  MSize prefix = 0, len, prec, pprec, width, need;
+
+  /* Figure out signed prefixes. */
+  if (STRFMT_TYPE(sf) == STRFMT_INT) {
+    if ((int64_t)k < 0) {
+      k = (uint64_t)-(int64_t)k;
+      prefix = 256 + '-';
+    } else if ((sf & STRFMT_F_PLUS)) {
+      prefix = 256 + '+';
+    } else if ((sf & STRFMT_F_SPACE)) {
+      prefix = 256 + ' ';
+    }
+  }
+
+  /* Convert number and store to fixed-size buffer in reverse order. */
+  prec = STRFMT_PREC(sf);
+  if ((int32_t)prec >= 0) sf &= ~STRFMT_F_ZERO;
+  if (k == 0) {  /* Special-case zero argument. */
+    if (prec != 0 ||
+        (sf & (STRFMT_T_OCT|STRFMT_F_ALT)) == (STRFMT_T_OCT|STRFMT_F_ALT))
+      *--q = '0';
+  } else if (!(sf & (STRFMT_T_HEX|STRFMT_T_OCT))) {  /* Decimal. */
+    uint32_t k2;
+    while ((k >> 32)) { *--q = (char)('0' + k % 10); k /= 10; }
+    k2 = (uint32_t)k;
+    do { *--q = (char)('0' + k2 % 10); k2 /= 10; } while (k2);
+  } else if ((sf & STRFMT_T_HEX)) {  /* Hex. */
+    const char *hexdig = (sf & STRFMT_F_UPPER) ? "0123456789ABCDEF" :
+                                                 "0123456789abcdef";
+    do { *--q = hexdig[(k & 15)]; k >>= 4; } while (k);
+    if ((sf & STRFMT_F_ALT)) prefix = 512 + ((sf & STRFMT_F_UPPER) ? 'X' : 'x');
+  } else {  /* Octal. */
+    do { *--q = (char)('0' + (uint32_t)(k & 7)); k >>= 3; } while (k);
+    if ((sf & STRFMT_F_ALT)) *--q = '0';
+  }
+
+  /* Calculate sizes. */
+  len = (MSize)(buf + sizeof(buf) - q);
+  if ((int32_t)len >= (int32_t)prec) prec = len;
+  width = STRFMT_WIDTH(sf);
+  pprec = prec + (prefix >> 8);
+  need = width > pprec ? width : pprec;
+  w = lj_buf_more(sb, need);
+#ifdef LUA_USE_ASSERT
+  ws = w;
+#endif
+
+  /* Format number with leading/trailing whitespace and zeros. */
+  if ((sf & (STRFMT_F_LEFT|STRFMT_F_ZERO)) == 0)
+    while (width-- > pprec) *w++ = ' ';
+  if (prefix) {
+    if ((char)prefix >= 'X') *w++ = '0';
+    *w++ = (char)prefix;
+  }
+  if ((sf & (STRFMT_F_LEFT|STRFMT_F_ZERO)) == STRFMT_F_ZERO)
+    while (width-- > pprec) *w++ = '0';
+  while (prec-- > len) *w++ = '0';
+  while (q < buf + sizeof(buf)) *w++ = *q++;  /* Add number itself. */
+  if ((sf & STRFMT_F_LEFT))
+    while (width-- > pprec) *w++ = ' ';
+
+  lj_assertX(need == (MSize)(w - ws), "miscalculated format size");
+  sb->w = w;
+  return sb;
+}
+
+/* Add number formatted as signed integer to buffer. */
+SBuf *lj_strfmt_putfnum_int(SBuf *sb, SFormat sf, lua_Number n)
+{
+  int64_t k = (int64_t)n;
+  if (checki32(k) && sf == STRFMT_INT)
+    return lj_strfmt_putint(sb, (int32_t)k);  /* Shortcut for plain %d. */
+  else
+    return lj_strfmt_putfxint(sb, sf, (uint64_t)k);
+}
+
+/* Add number formatted as unsigned integer to buffer. */
+SBuf *lj_strfmt_putfnum_uint(SBuf *sb, SFormat sf, lua_Number n)
+{
+  int64_t k;
+  if (n >= 9223372036854775808.0)
+    k = (int64_t)(n - 18446744073709551616.0);
+  else
+    k = (int64_t)n;
+  return lj_strfmt_putfxint(sb, sf, (uint64_t)k);
+}
+
+/* Format stack arguments to buffer. */
+int lj_strfmt_putarg(lua_State *L, SBuf *sb, int arg, int retry)
+{
+  int narg = (int)(L->top - L->base);
+  GCstr *fmt = lj_lib_checkstr(L, arg);
+  FormatState fs;
+  SFormat sf;
+  lj_strfmt_init(&fs, strdata(fmt), fmt->len);
+  while ((sf = lj_strfmt_parse(&fs)) != STRFMT_EOF) {
+    if (sf == STRFMT_LIT) {
+      lj_buf_putmem(sb, fs.str, fs.len);
+    } else if (sf == STRFMT_ERR) {
+      lj_err_callerv(L, LJ_ERR_STRFMT,
+                     strdata(lj_str_new(L, fs.str, fs.len)));
+    } else {
+      TValue *o = &L->base[arg++];
+      if (arg > narg)
+        lj_err_arg(L, arg, LJ_ERR_NOVAL);
+      switch (STRFMT_TYPE(sf)) {
+      case STRFMT_INT:
+        if (tvisint(o)) {
+          int32_t k = intV(o);
+          if (sf == STRFMT_INT)
+            lj_strfmt_putint(sb, k);  /* Shortcut for plain %d. */
+          else
+            lj_strfmt_putfxint(sb, sf, k);
+          break;
+        }
+#if LJ_HASFFI
+        if (tviscdata(o)) {
+          GCcdata *cd = cdataV(o);
+          if (cd->ctypeid == CTID_INT64 || cd->ctypeid == CTID_UINT64) {
+            lj_strfmt_putfxint(sb, sf, *(uint64_t *)cdataptr(cd));
+            break;
+          }
+        }
+#endif
+        lj_strfmt_putfnum_int(sb, sf, lj_lib_checknum(L, arg));
+        break;
+      case STRFMT_UINT:
+        if (tvisint(o)) {
+          lj_strfmt_putfxint(sb, sf, intV(o));
+          break;
+        }
+#if LJ_HASFFI
+        if (tviscdata(o)) {
+          GCcdata *cd = cdataV(o);
+          if (cd->ctypeid == CTID_INT64 || cd->ctypeid == CTID_UINT64) {
+            lj_strfmt_putfxint(sb, sf, *(uint64_t *)cdataptr(cd));
+            break;
+          }
+        }
+#endif
+        lj_strfmt_putfnum_uint(sb, sf, lj_lib_checknum(L, arg));
+        break;
+      case STRFMT_NUM:
+        lj_strfmt_putfnum(sb, sf, lj_lib_checknum(L, arg));
+        break;
+      case STRFMT_STR: {
+        MSize len;
+        const char *s;
+        cTValue *mo;
+        if (LJ_UNLIKELY(!tvisstr(o) && !tvisbuf(o)) && retry >= 0 &&
+            !tvisnil(mo = lj_meta_lookup(L, o, MM_tostring))) {
+          /* Call __tostring metamethod once. */
+          copyTV(L, L->top++, mo);
+          copyTV(L, L->top++, o);
+          lua_call(L, 1, 1);
+          o = &L->base[arg-1];  /* Stack may have been reallocated. */
+          copyTV(L, o, --L->top);  /* Replace inline for retry. */
+          if (retry < 2) {  /* Global buffer may have been overwritten. */
+            retry = 1;
+            break;
+          }
+        }
+        if (LJ_LIKELY(tvisstr(o))) {
+          len = strV(o)->len;
+          s = strVdata(o);
+#if LJ_HASBUFFER
+        } else if (tvisbuf(o)) {
+          SBufExt *sbx = bufV(o);
+          if (sbx == (SBufExt *)sb) lj_err_arg(L, arg+1, LJ_ERR_BUFFER_SELF);
+          len = sbufxlen(sbx);
+          s = sbx->r;
+#endif
+        } else {
+          GCstr *str = lj_strfmt_obj(L, o);
+          len = str->len;
+          s = strdata(str);
+        }
+        if ((sf & STRFMT_T_QUOTED))
+          strfmt_putquotedlen(sb, s, len);  /* No formatting. */
+        else
+          strfmt_putfstrlen(sb, sf, s, len);
+        break;
+        }
+      case STRFMT_CHAR:
+        lj_strfmt_putfchar(sb, sf, lj_lib_checkint(L, arg));
+        break;
+      case STRFMT_PTR:  /* No formatting. */
+        lj_strfmt_putptr(sb, lj_obj_ptr(G(L), o));
+        break;
+      default:
+        lj_assertL(0, "bad string format type");
+        break;
+      }
+    }
+  }
+  return retry;
+}
+
+/* -- Conversions to strings ---------------------------------------------- */
+
+/* Convert integer to string. */
+GCstr * LJ_FASTCALL lj_strfmt_int(lua_State *L, int32_t k)
+{
+  char buf[STRFMT_MAXBUF_INT];
+  MSize len = (MSize)(lj_strfmt_wint(buf, k) - buf);
+  return lj_str_new(L, buf, len);
+}
+
+/* Convert integer or number to string. */
+GCstr * LJ_FASTCALL lj_strfmt_number(lua_State *L, cTValue *o)
+{
+  return tvisint(o) ? lj_strfmt_int(L, intV(o)) : lj_strfmt_num(L, o);
+}
+
+#if LJ_HASJIT
+/* Convert char value to string. */
+GCstr * LJ_FASTCALL lj_strfmt_char(lua_State *L, int c)
+{
+  char buf[1];
+  buf[0] = c;
+  return lj_str_new(L, buf, 1);
+}
+#endif
+
+/* Raw conversion of object to string. */
+GCstr * LJ_FASTCALL lj_strfmt_obj(lua_State *L, cTValue *o)
+{
+  if (tvisstr(o)) {
+    return strV(o);
+  } else if (tvisnumber(o)) {
+    return lj_strfmt_number(L, o);
+  } else if (tvisnil(o)) {
+    return lj_str_newlit(L, "nil");
+  } else if (tvisfalse(o)) {
+    return lj_str_newlit(L, "false");
+  } else if (tvistrue(o)) {
+    return lj_str_newlit(L, "true");
+  } else {
+    char buf[8+2+2+16], *p = buf;
+    p = lj_buf_wmem(p, lj_typename(o), (MSize)strlen(lj_typename(o)));
+    *p++ = ':'; *p++ = ' ';
+    if (tvisfunc(o) && isffunc(funcV(o))) {
+      p = lj_buf_wmem(p, "builtin#", 8);
+      p = lj_strfmt_wint(p, funcV(o)->c.ffid);
+    } else {
+      p = lj_strfmt_wptr(p, lj_obj_ptr(G(L), o));
+    }
+    return lj_str_new(L, buf, (size_t)(p - buf));
+  }
+}
+
+/* -- Internal string formatting ------------------------------------------ */
+
+/*
+** These functions are only used for lua_pushfstring(), lua_pushvfstring()
+** and for internal string formatting (e.g. error messages). Caveat: unlike
+** string.format(), only a limited subset of formats and flags are supported!
+**
+** LuaJIT has support for a couple more formats than Lua 5.1/5.2:
+** - %d %u %o %x with full formatting, 32 bit integers only.
+** - %f and other FP formats are really %.14g.
+** - %s %c %p without formatting.
+*/
+
+/* Push formatted message as a string object to Lua stack. va_list variant. */
+const char *lj_strfmt_pushvf(lua_State *L, const char *fmt, va_list argp)
+{
+  SBuf *sb = lj_buf_tmp_(L);
+  FormatState fs;
+  SFormat sf;
+  GCstr *str;
+  lj_strfmt_init(&fs, fmt, (MSize)strlen(fmt));
+  while ((sf = lj_strfmt_parse(&fs)) != STRFMT_EOF) {
+    switch (STRFMT_TYPE(sf)) {
+    case STRFMT_LIT:
+      lj_buf_putmem(sb, fs.str, fs.len);
+      break;
+    case STRFMT_INT:
+      lj_strfmt_putfxint(sb, sf, va_arg(argp, int32_t));
+      break;
+    case STRFMT_UINT:
+      lj_strfmt_putfxint(sb, sf, va_arg(argp, uint32_t));
+      break;
+    case STRFMT_NUM:
+      lj_strfmt_putfnum(sb, STRFMT_G14, va_arg(argp, lua_Number));
+      break;
+    case STRFMT_STR: {
+      const char *s = va_arg(argp, char *);
+      if (s == NULL) s = "(null)";
+      lj_buf_putmem(sb, s, (MSize)strlen(s));
+      break;
+      }
+    case STRFMT_CHAR:
+      lj_buf_putb(sb, va_arg(argp, int));
+      break;
+    case STRFMT_PTR:
+      lj_strfmt_putptr(sb, va_arg(argp, void *));
+      break;
+    case STRFMT_ERR:
+    default:
+      lj_buf_putb(sb, '?');
+      lj_assertL(0, "bad string format near offset %d", fs.len);
+      break;
+    }
+  }
+  str = lj_buf_str(L, sb);
+  setstrV(L, L->top, str);
+  incr_top(L);
+  return strdata(str);
+}
+
+/* Push formatted message as a string object to Lua stack. Vararg variant. */
+const char *lj_strfmt_pushf(lua_State *L, const char *fmt, ...)
+{
+  const char *msg;
+  va_list argp;
+  va_start(argp, fmt);
+  msg = lj_strfmt_pushvf(L, fmt, argp);
+  va_end(argp);
+  return msg;
+}
+