This introduces a few new APIs for dealing with strings. One to split a char * into a char **, another to join a char ** into a char *, and finally one to free a char **
Do we also want to migrate virsh.c:vshStringToArray() to this file, with its additional magic of supporting ',,' as an escape sequence for literal comma in one of the strings being split?
There is a simple test suite to validate the edge cases too. No more need to use the horrible strtok_r() API, or hand-written code for splitting strings.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com> --- src/Makefile.am | 1 + src/libvirt_private.syms | 6 ++ src/util/virstring.c | 129 +++++++++++++++++++++++++++++++++++++ src/util/virstring.h | 36 +++++++++++ tests/Makefile.am | 6 ++ tests/virstringtest.c | 164 +++++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 342 insertions(+) create mode 100644 src/util/virstring.c create mode 100644 src/util/virstring.h create mode 100644 tests/virstringtest.c
+ +char **virStringSplit(const char *string, + const char *delim, + size_t max_tokens) +{ + char **tokens = NULL; + size_t ntokens = 0; + size_t maxtokens = 0; + const char *remainder = string; + char *tmp; + size_t i; + + if (max_tokens < 1)
Effectively 'if (!max_tokens)'
+ +char *virStringJoin(const char **strings, + const char *delim) +{
Should this function have a third argument that says how many elements are in strings (and leave it 0 if strings is NULL-terminated)? Otherwise, callers will have to ensure that there is a trailing NULL element in strings, instead of being able to specifically request the joining of an exact amount of strings.
+ size_t len = 0; + size_t delimlen = strlen(delim); + const char **tmp = strings; + char *string; + char *offset; + + while (tmp && *tmp) { + len += strlen(*tmp); + len += delimlen; + tmp++; + }
Would it be any easier to write this function in terms of virBuffer, instead of rolling it by hand? Untested: char *virStringJoin(const char **strings, const char *delim) { virBuffer buf = VIR_BUFFER_INITIALIZER; if (strings && *strings) { virBufferAdd(&buf, *strings, 0); while (*++strings) { virBufferAdd(&buf, delim, 0); virBufferAdd(*strings); } } return virBufferContentAndReset(&buf); }
+void virStringFreeList(char **strings)
Another function that might benefit from a length argument, rather than forcing the user to pass in a NULL-terminated list; in which case, it would then be usable in the no_memory label of the split function, rather than your current hand-rolled cleanup loop (since that label is a case of not having a NULL terminator).
+ +char **virStringSplit(const char *string, + const char *delim, + size_t max_tokens);
Worth marking ATTRIBUTE_NONNULL(2)? It looks like you intend to allow NULL for arg 1 though (in which case the return is also NULL).
+ +char *virStringJoin(const char **strings, + const char *delim);
Worth marking ATTRIBUTE_NONNULL(2)?
+++ b/tests/Makefile.am @@ -95,6 +95,7 @@ test_programs = virshtest sockettest \ virauthconfigtest \ virbitmaptest \ virlockspacetest \ + virstringtest \
Does .gitignore need to be updated for this binary?
+++ b/tests/virstringtest.c @@ -0,0 +1,164 @@ +/* + * Copyright (C) 2011 Red Hat, Inc.
2012
+static int +mymain(void) +{ + int ret = 0; + + signal(SIGPIPE, SIG_IGN);
Isn't this already taken care of in the top-level main() before calling into mymain()?