strjoin()

diff --git a/ccan/string/string.c b/ccan/string/string.c
index d3d17bbd3156eb065ece87e94f28810fddf7a465..b1de8eda915bbf3ee81fc2e9f1df96603eb6084b 100644 (file)
--- a/ccan/string/string.c
+++ b/ccan/string/string.c
@@ -30,4 +30,15 @@ char **strsplit(const void *ctx, const char *string, const char *delims,
                *nump = num;
        return lines;
 }
                *nump = num;
        return lines;
 }

-       
+
+char *strjoin(const void *ctx, char *strings[], const char *delim)
+{
+       unsigned int i;
+       char *ret = talloc_strdup(ctx, "");
+
+       for (i = 0; strings[i]; i++) {
+               ret = talloc_append_string(ret, strings[i]);
+               ret = talloc_append_string(ret, delim);
+       }
+       return ret;
+}

diff --git a/ccan/string/string.h b/ccan/string/string.h
index 3b6367479783aba3c0dfa78965872af7d192bb72..b2cd814c1bde23179f53903084a8f271bb549e17 100644 (file)
--- a/ccan/string/string.h
+++ b/ccan/string/string.h
@@ -54,7 +54,8 @@ static inline bool strends(const char *str, const char *postfix)
  * This function splits a single string into multiple strings.  The
  * original string is untouched: an array is allocated (using talloc)
  * pointing to copies of each substring.  Multiple delimiters result
  * This function splits a single string into multiple strings.  The
  * original string is untouched: an array is allocated (using talloc)
  * pointing to copies of each substring.  Multiple delimiters result

- * in empty substrings.
+ * in empty substrings.  By definition, no delimiters will appear in
+ * the substrings.

  *
  * The final char * in the array will be NULL, so you can use this or
  * @nump to find the array length.
  *
  * The final char * in the array will be NULL, so you can use this or
  * @nump to find the array length.


@@ -76,4 +77,29 @@ static inline bool strends(const char *str, const char *postfix)
  */
 char **strsplit(const void *ctx, const char *string, const char *delims,
                 unsigned int *nump);
  */
 char **strsplit(const void *ctx, const char *string, const char *delims,
                 unsigned int *nump);

+
+/**
+ * strjoin - Join an array of substrings into one long string
+ * @ctx: the context to tallocate from (often NULL)
+ * @strings: the NULL-terminated array of strings to join
+ * @delim: the delimiter to insert between the strings
+ *
+ * This function joins an array of strings into a single string.  The
+ * return value is allocated using talloc.  Each string in @strings is
+ * followed by a copy of @delim.
+ *
+ * Example:
+ *     // Append the string "--EOL" to each line.
+ *     char *append_to_all_lines(const char *string)
+ *     {
+ *             char **lines, *ret;
+ *             unsigned int i, num, newnum;
+ *
+ *             lines = strsplit(NULL, string, "\n", NULL);
+ *             ret = strjoin(NULL, lines, "-- EOL\n");
+ *             talloc_free(lines);
+ *             return ret;
+ *     }
+ */
+char *strjoin(const void *ctx, char *strings[], const char *delim);

 #endif /* CCAN_STRING_H */
 #endif /* CCAN_STRING_H */

diff --git a/ccan/string/test/run.c b/ccan/string/test/run.c
index 089bfd3e4fda6a72be3f157b3a1ca60617b71d0c..02403d24511300a68f05d182d68fa98f66a6503e 100644 (file)
--- a/ccan/string/test/run.c
+++ b/ccan/string/test/run.c
@@ -7,7 +7,9 @@
 /* FIXME: ccanize */
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
 
 /* FIXME: ccanize */
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
 

-static char *substrings[] = { "far", "bar", "baz", "b", "ba", "z", "ar" };
+static char *substrings[] = { "far", "bar", "baz", "b", "ba", "z", "ar", NULL };
+
+#define NUM_SUBSTRINGS (ARRAY_SIZE(substrings) - 1)

 
 static char *strdup_rev(const char *s)
 {
 
 static char *strdup_rev(const char *s)
 {


@@ -22,13 +24,13 @@ static char *strdup_rev(const char *s)
 int main(int argc, char *argv[])
 {
        unsigned int i, j, n;
 int main(int argc, char *argv[])
 {
        unsigned int i, j, n;

-       char **split;
+       char **split, *str;

        void *ctx;
        void *ctx;

-       char *strings[ARRAY_SIZE(substrings) * ARRAY_SIZE(substrings)];
+       char *strings[NUM_SUBSTRINGS * NUM_SUBSTRINGS];

 
        n = 0;
 
        n = 0;

-       for (i = 0; i < ARRAY_SIZE(substrings); i++) {
-               for (j = 0; j < ARRAY_SIZE(substrings); j++) {
+       for (i = 0; i < NUM_SUBSTRINGS; i++) {
+               for (j = 0; j < NUM_SUBSTRINGS; j++) {

                        strings[n] = malloc(strlen(substrings[i])
                                            + strlen(substrings[j]) + 1);
                        sprintf(strings[n++], "%s%s",
                        strings[n] = malloc(strlen(substrings[i])
                                            + strlen(substrings[j]) + 1);
                        sprintf(strings[n++], "%s%s",


@@ -36,7 +38,7 @@ int main(int argc, char *argv[])
                }
        }
 
                }
        }
 

-       plan_tests(n * n * 5 + 16);
+       plan_tests(n * n * 5 + 19);

        for (i = 0; i < n; i++) {
                for (j = 0; j < n; j++) {
                        unsigned int k, identical = 0;
        for (i = 0; i < n; i++) {
                for (j = 0; j < n; j++) {
                        unsigned int k, identical = 0;


@@ -104,6 +106,16 @@ int main(int argc, char *argv[])
        split = strsplit(ctx, "hello  world", "o ", NULL);
        ok1(talloc_parent(split) == ctx);
        talloc_free(ctx);
        split = strsplit(ctx, "hello  world", "o ", NULL);
        ok1(talloc_parent(split) == ctx);
        talloc_free(ctx);

+
+       str = strjoin(NULL, substrings, ", ");
+       ok1(streq(str, "far, bar, baz, b, ba, z, ar, "));
+       ctx = str;
+       str = strjoin(ctx, substrings, "");
+       ok1(streq(str, "farbarbazbbazar"));
+       ok1(talloc_parent(str) == ctx);
+       talloc_free(ctx);
+
+

        
        return exit_status();
 }                              
        
        return exit_status();
 }