From: Denys Vlasenko Date: Wed, 2 Jan 2019 04:03:53 +0000 (+0100) Subject: bc: speed up string printing, fix print "" X-Git-Tag: 1_31_0~246 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=266bec8ba76898c5602e54fb3460c4af42f38af0;p=oweals%2Fbusybox.git bc: speed up string printing, fix print "" function old new delta static.esc - 9 +9 zxc_program_print 681 683 +2 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 1/0 up/down: 11/0) Total: 11 bytes text data bss dec hex filename 979144 485 7296 986925 f0f2d busybox_old 979062 485 7296 986843 f0edb busybox_unstripped Signed-off-by: Denys Vlasenko --- diff --git a/miscutils/bc.c b/miscutils/bc.c index 1b9cdce5e..bb91216c2 100644 --- a/miscutils/bc.c +++ b/miscutils/bc.c @@ -5359,7 +5359,7 @@ static char *xc_program_name(char *code, size_t *bgn) static void xc_program_printString(const char *str) { #if ENABLE_DC - if (!str[0]) { + if (!str[0] && IS_DC) { // Example: echo '[]ap' | dc // should print two bytes: 0x00, 0x0A bb_putchar('\0'); @@ -5367,46 +5367,25 @@ static void xc_program_printString(const char *str) } #endif while (*str) { - int c = *str++; - if (c != '\\' || !*str) - bb_putchar(c); - else { + char c = *str++; + if (c == '\\') { + static const char esc[] ALIGN1 = "nabfrt""e\\"; + char *n; + c = *str++; - switch (c) { - case 'a': - bb_putchar('\a'); - break; - case 'b': - bb_putchar('\b'); - break; - case '\\': - case 'e': - bb_putchar('\\'); - break; - case 'f': - bb_putchar('\f'); - break; - case 'n': - bb_putchar('\n'); - G.prog.nchars = SIZE_MAX; - break; - case 'r': - bb_putchar('\r'); - break; - case 'q': - bb_putchar('"'); - break; - case 't': - bb_putchar('\t'); - break; - default: - // Just print the backslash and following character. + n = strchr(esc, c); // note: c can be NUL + if (!n) { + // Just print the backslash and following character bb_putchar('\\'); ++G.prog.nchars; - bb_putchar(c); - break; + } else { + if (n - esc == 0) // "\n" ? + G.prog.nchars = SIZE_MAX; + c = "\n\a\b\f\r\t""\\\\""\\"[n - esc]; + // n a b f r t e \ \ } } + putchar(c); ++G.prog.nchars; } } @@ -5631,16 +5610,15 @@ static BC_STATUS zxc_program_print(char inst, size_t idx) str = *xc_program_str(idx); if (inst == XC_INST_PRINT_STR) { - for (;;) { - char c = *str++; - if (c == '\0') break; - bb_putchar(c); - ++G.prog.nchars; - if (c == '\n') G.prog.nchars = 0; - } + char *nl; + G.prog.nchars += printf("%s", str); + nl = strrchr(str, '\n'); + if (nl) + G.prog.nchars = strlen(nl + 1); } else { xc_program_printString(str); - if (inst == XC_INST_PRINT) bb_putchar('\n'); + if (inst == XC_INST_PRINT) + bb_putchar('\n'); } } diff --git a/testsuite/bc.tests b/testsuite/bc.tests index 13525ea52..fbcfff2e4 100755 --- a/testsuite/bc.tests +++ b/testsuite/bc.tests @@ -149,6 +149,12 @@ testing "bc (!a&&b)" \ "0\n" \ "" "(!a&&b)" +# check that dc code is not messing this up (no NUL printing!) +testing "bc print \"\"" \ + "bc" \ + "" \ + "" "print \"\"" + testing "bc print 1,2,3" \ "bc" \ "123" \