From: Filipe Brandenburger <filbranden@google.com>
Date: Mon, 31 Aug 2015 02:16:50 +0000 (-0700)
Subject: extract_first_word: Refactor allocation in empty argument case
X-Git-Tag: v226.4~1^2~101
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=d58deedf28351f217c1348604eab87ec075975c2;ds=sidebyside

extract_first_word: Refactor allocation in empty argument case

This covers the case where an argument is an empty string, such as ''.

Instead of allocating the empty string in the individual conditions when
state == VALUE, just always allocate it at the end of state == START, at
which point we know we will have an argument.

Tested that test-util keeps passing after the refactor.

Follow up to: 14e685c29d5b317b815e3e9f056648027852b07e
---

diff --git a/src/basic/util.c b/src/basic/util.c
index c6b48ef30..fbd6ff5d9 100644
--- a/src/basic/util.c
+++ b/src/basic/util.c
@@ -5859,25 +5859,25 @@ int extract_first_word(const char **p, char **ret, const char *separators, Extra
                                 break;
                         }
 
+                        /* We found a non-blank character, so we will always
+                         * want to return a string (even if it is empty),
+                         * allocate it here. */
+                        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)) {
-                                if (!GREEDY_REALLOC(s, allocated, sz+1))
-                                        return -ENOMEM;
-
+                        else if (c == '\'' && (flags & EXTRACT_QUOTES))
                                 state = SINGLE_QUOTE;
-                        } else if (c == '\\')
+                        else if (c == '\\')
                                 state = VALUE_ESCAPE;
-                        else if (c == '\"' && (flags & EXTRACT_QUOTES)) {
-                                if (!GREEDY_REALLOC(s, allocated, sz+1))
-                                        return -ENOMEM;
-
+                        else if (c == '\"' && (flags & EXTRACT_QUOTES))
                                 state = DOUBLE_QUOTE;
-                        } else if (strchr(separators, c)) {
+                        else if (strchr(separators, c)) {
                                 if (flags & EXTRACT_DONT_COALESCE_SEPARATORS) {
                                         (*p) ++;
                                         goto finish_force_next;