[PATCH 1/7] ash: code shrink around varvalue
Ron Yorston
rmy at frippery.org
Fri May 15 10:31:46 UTC 2015
Based on commit c989d72 from git://git.kernel.org/pub/scm/utils/dash/dash.git
by Herbert Xu
function old new delta
memtodest 129 164 +35
varvalue 853 767 -86
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 35/-86) Total: -51 bytes
Signed-off-by: Ron Yorston <rmy at pobox.com>
---
shell/ash.c | 84 ++++++++++++++++++++++++++++---------------------------------
1 file changed, 38 insertions(+), 46 deletions(-)
diff --git a/shell/ash.c b/shell/ash.c
index 7af8842..a81922a 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -5539,6 +5539,11 @@ ash_arith(const char *s)
#define RMESCAPE_GROW 0x8 /* Grow strings instead of stalloc */
#define RMESCAPE_HEAP 0x10 /* Malloc strings instead of stalloc */
+/* Add CTLESC when necessary. */
+#define QUOTES_ESC (EXP_FULL | EXP_CASE | EXP_REDIR)
+/* Do not skip NUL characters. */
+#define QUOTES_KEEPNUL EXP_TILDE
+
/*
* Structure specifying which parts of the string should be searched
* for IFS characters.
@@ -5695,29 +5700,34 @@ preglob(const char *pattern, int quoted, int flag)
static void
memtodest(const char *p, size_t len, int syntax, int quotes)
{
- char *q = expdest;
+ char *q;
+
+ if (!len)
+ return;
- q = makestrspace(quotes ? len * 2 : len, q);
+ q = makestrspace((quotes & QUOTES_ESC) ? len * 2 : len, expdest);
- while (len--) {
+ do {
unsigned char c = *p++;
- if (c == '\0')
- continue;
- if (quotes) {
+ if (c) {
int n = SIT(c, syntax);
- if (n == CCTL || n == CBACK)
+ if ((quotes & QUOTES_ESC) &&
+ (n == CCTL || n == CBACK))
USTPUTC(CTLESC, q);
- }
+ } else if (!(quotes & QUOTES_KEEPNUL))
+ continue;
USTPUTC(c, q);
- }
+ } while (--len);
expdest = q;
}
-static void
+static size_t
strtodest(const char *p, int syntax, int quotes)
{
- memtodest(p, strlen(p), syntax, quotes);
+ size_t len = strlen(p);
+ memtodest(p, len, syntax, quotes);
+ return len;
}
/*
@@ -5790,7 +5800,7 @@ exptilde(char *startp, char *p, int flags)
char *name;
struct passwd *pw;
const char *home;
- int quotes = flags & (EXP_FULL | EXP_CASE | EXP_REDIR);
+ int quotes = flags & QUOTES_ESC;
name = p + 1;
@@ -6043,7 +6053,7 @@ argstr(char *p, int flags, struct strlist *var_str_list)
'\0'
};
const char *reject = spclchars;
- int quotes = flags & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */
+ int quotes = flags & QUOTES_ESC;
int breakall = flags & EXP_WORD;
int inquotes;
size_t length;
@@ -6608,13 +6618,16 @@ varvalue(char *name, int varflags, int flags, struct strlist *var_str_list)
const char *p;
int num;
int i;
- int sepq = 0;
ssize_t len = 0;
- int subtype = varflags & VSTYPE;
- int quotes = flags & (EXP_FULL | EXP_CASE | EXP_REDIR);
+ int sep;
int quoted = varflags & VSQUOTE;
+ int subtype = varflags & VSTYPE;
+ int discard = subtype == VSPLUS || subtype == VSLENGTH;
+ int quotes = (discard ? 0 : (flags & QUOTES_ESC)) | QUOTES_KEEPNUL;
int syntax = quoted ? DQSYNTAX : BASESYNTAX;
+ sep = quoted ? ((flags & EXP_FULL) << CHAR_BIT) : 0;
+
switch (*name) {
case '$':
num = rootpid;
@@ -6649,7 +6662,7 @@ varvalue(char *name, int varflags, int flags, struct strlist *var_str_list)
break;
case '@': {
char **ap;
- int sep;
+ char sepc;
if (quoted && (flags & EXP_FULL)) {
/* note: this is not meant as PEOF value */
@@ -6659,39 +6672,20 @@ varvalue(char *name, int varflags, int flags, struct strlist *var_str_list)
/* fall through */
case '*':
sep = ifsset() ? (unsigned char)(ifsval()[0]) : ' ';
- i = SIT(sep, syntax);
- if (quotes && (i == CCTL || i == CBACK))
- sepq = 1;
param:
ap = shellparam.p;
+ sepc = sep;
if (!ap)
return -1;
while ((p = *ap++) != NULL) {
- size_t partlen;
-
- partlen = strlen(p);
- len += partlen;
-
- if (!(subtype == VSPLUS || subtype == VSLENGTH))
- memtodest(p, partlen, syntax, quotes);
+ len += strtodest(p, syntax, quotes);
if (*ap && sep) {
- char *q;
-
len++;
- if (subtype == VSPLUS || subtype == VSLENGTH) {
- continue;
- }
- q = expdest;
- if (sepq)
- STPUTC(CTLESC, q);
- /* note: may put NUL despite sep != 0
- * (see sep = 1 << CHAR_BIT above) */
- STPUTC(sep, q);
- expdest = q;
+ memtodest(&sepc, 1, syntax, quotes);
}
}
- return len;
+ break;
} /* case '@' and '*' */
case '0':
case '1':
@@ -6740,9 +6734,7 @@ varvalue(char *name, int varflags, int flags, struct strlist *var_str_list)
if (!p)
return -1;
- len = strlen(p);
- if (!(subtype == VSPLUS || subtype == VSLENGTH))
- memtodest(p, len, syntax, quotes);
+ len = strtodest(p, syntax, quotes);
#if ENABLE_UNICODE_SUPPORT
if (subtype == VSLENGTH && len > 0) {
reinit_unicode_for_ash();
@@ -6751,10 +6743,10 @@ varvalue(char *name, int varflags, int flags, struct strlist *var_str_list)
}
}
#endif
- return len;
+ break;
}
- if (subtype == VSPLUS || subtype == VSLENGTH)
+ if (discard)
STADJUST(-len, expdest);
return len;
}
@@ -6870,7 +6862,7 @@ evalvar(char *p, int flags, struct strlist *var_str_list)
patloc = expdest - (char *)stackblock();
if (NULL == subevalvar(p, /* varname: */ NULL, patloc, subtype,
startloc, varflags,
- /* quotes: */ flags & (EXP_FULL | EXP_CASE | EXP_REDIR),
+ /* quotes: */ flags & QUOTES_ESC,
var_str_list)
) {
int amount = expdest - (
--
2.1.0
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