diff options
Diffstat (limited to 'daemon/guestfsd.c')
-rw-r--r-- | daemon/guestfsd.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/daemon/guestfsd.c b/daemon/guestfsd.c index eeb84bd1..406c1041 100644 --- a/daemon/guestfsd.c +++ b/daemon/guestfsd.c @@ -587,6 +587,60 @@ commandrv (char **stdoutput, char **stderror, char * const* const argv) return -1; } +/* Split an output string into a NULL-terminated list of lines. + * Typically this is used where we have run an external command + * which has printed out a list of things, and we want to return + * an actual list. + * + * The corner cases here are quite tricky. Note in particular: + * + * "" -> [] + * "\n" -> [""] + * "a\nb" -> ["a"; "b"] + * "a\nb\n" -> ["a"; "b"] + * "a\nb\n\n" -> ["a"; "b"; ""] + * + * The original string is written over and destroyed by this + * function (which is usually OK because it's the 'out' string + * from command()). You can free the original string, because + * add_string() strdups the strings. + */ +char ** +split_lines (char *str) +{ + char **lines = NULL; + int size = 0, alloc = 0; + char *p, *pend; + + if (strcmp (str, "") == 0) + goto empty_list; + + p = str; + while (p) { + /* Empty last line? */ + if (p[0] == '\0') + break; + + pend = strchr (p, '\n'); + if (pend) { + *pend = '\0'; + pend++; + } + + if (add_string (&lines, &size, &alloc, p) == -1) { + return NULL; + } + + p = pend; + } + + empty_list: + if (add_string (&lines, &size, &alloc, NULL) == -1) + return NULL; + + return lines; +} + /* Quote 'in' for the shell, and write max len-1 bytes to out. The * result will be NUL-terminated, even if it is truncated. * |