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author | Herbert Xu <herbert@gondor.apana.org.au> | 2018-03-09 00:14:02 +0800 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2018-03-22 00:29:58 +0800 |
commit | ab1cecb4047864afb247a6ed691e7f59ce716f2c (patch) | |
tree | 4e4914acd4854f273fa7da4af24f7b86c83672fd /src/expand.c | |
parent | parser: use pgetc_eatbnl() in more places (diff) | |
download | dash-ab1cecb4047864afb247a6ed691e7f59ce716f2c.tar.gz dash-ab1cecb4047864afb247a6ed691e7f59ce716f2c.zip |
parser: Add syntax stack for recursive parsing
Without a stack of syntaxes we cannot correctly these two cases together: "${a#'$$'}" "${a#"${b-'$$'}"}" A recursive parser also helps in some other corner cases such as nested arithmetic expansion with paratheses. This patch adds a syntax stack allocated from the stack using alloca. As a side-effect this allows us to remove the naked backslashes for patterns within double-quotes, which means that EXP_QPAT also has to go. This patch also fixes removes any backslashes that precede right braces when they are present within a parameter expansion context, and backslashes that precede double quotes within inner double quotes inside a parameter expansion in a here-document context. The idea of a recursive parser is based on a patch by Harald van Dijk. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'src/expand.c')
-rw-r--r-- | src/expand.c | 27 |
1 files changed, 7 insertions, 20 deletions
diff --git a/src/expand.c b/src/expand.c index adcb70e..705fef7 100644 --- a/src/expand.c +++ b/src/expand.c @@ -85,7 +85,7 @@ #define RMESCAPE_HEAP 0x10 /* Malloc strings instead of stalloc */ /* Add CTLESC when necessary. */ -#define QUOTES_ESC (EXP_FULL | EXP_CASE | EXP_QPAT) +#define QUOTES_ESC (EXP_FULL | EXP_CASE) /* Do not skip NUL characters. */ #define QUOTES_KEEPNUL EXP_TILDE @@ -335,16 +335,6 @@ addquote: case CTLESC: startloc++; length++; - - /* - * Quoted parameter expansion pattern: remove quote - * unless inside inner quotes or we have a literal - * backslash. - */ - if (((flag | inquotes) & (EXP_QPAT | EXP_QUOTED)) == - EXP_QPAT && *p != '\\') - break; - goto addquote; case CTLVAR: p = evalvar(p, flag | inquotes); @@ -653,8 +643,7 @@ subevalvar(char *p, char *str, int strloc, int subtype, int startloc, int varfla char *(*scan)(char *, char *, char *, char *, int , int); argstr(p, EXP_TILDE | (subtype != VSASSIGN && subtype != VSQUESTION ? - (flag & (EXP_QUOTED | EXP_QPAT) ? - EXP_QPAT : EXP_CASE) : 0)); + EXP_CASE : 0)); STPUTC('\0', expdest); argbackq = saveargbackq; startp = stackblock() + startloc; @@ -1646,7 +1635,6 @@ char * _rmescapes(char *str, int flag) { char *p, *q, *r; - unsigned inquotes; int notescaped; int globbing; @@ -1676,24 +1664,23 @@ _rmescapes(char *str, int flag) q = mempcpy(q, str, len); } } - inquotes = 0; globbing = flag & RMESCAPE_GLOB; notescaped = globbing; while (*p) { if (*p == (char)CTLQUOTEMARK) { - inquotes = ~inquotes; p++; notescaped = globbing; continue; } + if (*p == '\\') { + /* naked back slash */ + notescaped = 0; + goto copy; + } if (*p == (char)CTLESC) { p++; if (notescaped) *q++ = '\\'; - } else if (*p == '\\' && !inquotes) { - /* naked back slash */ - notescaped = 0; - goto copy; } notescaped = globbing; copy: |