From 4cbf8afa0487b75525313b586853823ba5763d8e Mon Sep 17 00:00:00 2001 From: Filipe Brandenburger Date: Thu, 22 Oct 2015 23:12:31 -0700 Subject: util: Replace state with separate booleans in extract_first_word This simplifies the logic and uniformizes the way single and double quotes are handled. In the end, the code is about 40 lines shorter. Tested by running the excellent test cases from test-util. Also installed the systemd binaries including this patch and booted a system with it, everything looked normal. --- src/basic/util.c | 139 ++++++++++++++++++++----------------------------------- 1 file changed, 50 insertions(+), 89 deletions(-) (limited to 'src/basic') diff --git a/src/basic/util.c b/src/basic/util.c index 3989b415fa..d782bc6bdd 100644 --- a/src/basic/util.c +++ b/src/basic/util.c @@ -5815,16 +5815,10 @@ int extract_first_word(const char **p, char **ret, const char *separators, Extra size_t allocated = 0, sz = 0; int r; - enum { - START, - VALUE, - VALUE_ESCAPE, - SINGLE_QUOTE, - SINGLE_QUOTE_ESCAPE, - DOUBLE_QUOTE, - DOUBLE_QUOTE_ESCAPE, - SEPARATOR, - } state = START; + char quote = 0; /* 0 or ' or " */ + bool backslash = false; /* whether we've just seen a backslash */ + bool separator = false; /* whether we've just seen a separator */ + bool start = true; /* false means we're looking at a value */ assert(p); assert(ret); @@ -5844,9 +5838,7 @@ int extract_first_word(const char **p, char **ret, const char *separators, Extra for (;;) { char c = **p; - switch (state) { - - case START: + if (start) { if (flags & EXTRACT_DONT_COALESCE_SEPARATORS) if (!GREEDY_REALLOC(s, allocated, sz+1)) return -ENOMEM; @@ -5854,11 +5846,10 @@ int extract_first_word(const char **p, char **ret, const char *separators, Extra if (c == 0) goto finish_force_terminate; else if (strchr(separators, c)) { - if (flags & EXTRACT_DONT_COALESCE_SEPARATORS) { - (*p) ++; + (*p) ++; + if (flags & EXTRACT_DONT_COALESCE_SEPARATORS) goto finish_force_next; - } - break; + continue; } /* We found a non-blank character, so we will always @@ -5867,78 +5858,16 @@ int extract_first_word(const char **p, char **ret, const char *separators, Extra if (!GREEDY_REALLOC(s, allocated, sz+1)) return -ENOMEM; - state = VALUE; - /* fallthrough */ - - case VALUE: - if (c == 0) - goto finish_force_terminate; - else if (c == '\'' && (flags & EXTRACT_QUOTES)) - state = SINGLE_QUOTE; - else if (c == '\\') - state = VALUE_ESCAPE; - else if (c == '\"' && (flags & EXTRACT_QUOTES)) - state = DOUBLE_QUOTE; - else if (strchr(separators, c)) { - if (flags & EXTRACT_DONT_COALESCE_SEPARATORS) { - (*p) ++; - goto finish_force_next; - } - state = SEPARATOR; - } else { - if (!GREEDY_REALLOC(s, allocated, sz+2)) - return -ENOMEM; - - s[sz++] = c; - } - - break; - - case SINGLE_QUOTE: - if (c == 0) { - if (flags & EXTRACT_RELAX) - goto finish_force_terminate; - return -EINVAL; - } else if (c == '\'') - state = VALUE; - else if (c == '\\') - state = SINGLE_QUOTE_ESCAPE; - else { - if (!GREEDY_REALLOC(s, allocated, sz+2)) - return -ENOMEM; - - s[sz++] = c; - } - - break; - - case DOUBLE_QUOTE: - if (c == 0) { - if (flags & EXTRACT_RELAX) - goto finish_force_terminate; - return -EINVAL; - } else if (c == '\"') - state = VALUE; - else if (c == '\\') - state = DOUBLE_QUOTE_ESCAPE; - else { - if (!GREEDY_REALLOC(s, allocated, sz+2)) - return -ENOMEM; - - s[sz++] = c; - } - - break; + start = false; + } - case SINGLE_QUOTE_ESCAPE: - case DOUBLE_QUOTE_ESCAPE: - case VALUE_ESCAPE: + if (backslash) { if (!GREEDY_REALLOC(s, allocated, sz+7)) return -ENOMEM; if (c == 0) { if ((flags & EXTRACT_CUNESCAPE_RELAX) && - (state == VALUE_ESCAPE || flags & EXTRACT_RELAX)) { + (!quote || flags & EXTRACT_RELAX)) { /* If we find an unquoted trailing backslash and we're in * EXTRACT_CUNESCAPE_RELAX mode, keep it verbatim in the * output. @@ -5977,17 +5906,49 @@ int extract_first_word(const char **p, char **ret, const char *separators, Extra s[sz++] = c; end_escape: - state = (state == SINGLE_QUOTE_ESCAPE) ? SINGLE_QUOTE : - (state == DOUBLE_QUOTE_ESCAPE) ? DOUBLE_QUOTE : - VALUE; - break; + backslash = false; + + } else if (quote) { /* inside either single or double quotes */ + if (c == 0) { + if (flags & EXTRACT_RELAX) + goto finish_force_terminate; + return -EINVAL; + } else if (c == quote) /* found the end quote */ + quote = 0; + else if (c == '\\') + backslash = true; + else { + if (!GREEDY_REALLOC(s, allocated, sz+2)) + return -ENOMEM; + + s[sz++] = c; + } - case SEPARATOR: + } else if (separator) { if (c == 0) goto finish_force_terminate; if (!strchr(separators, c)) goto finish; - break; + + } else { + if (c == 0) + goto finish_force_terminate; + else if ((c == '\'' || c == '"') && (flags & EXTRACT_QUOTES)) + quote = c; + else if (c == '\\') + backslash = true; + else if (strchr(separators, c)) { + if (flags & EXTRACT_DONT_COALESCE_SEPARATORS) { + (*p) ++; + goto finish_force_next; + } + separator = true; + } else { + if (!GREEDY_REALLOC(s, allocated, sz+2)) + return -ENOMEM; + + s[sz++] = c; + } } (*p) ++; -- cgit v1.2.3-54-g00ecf