HDFFV-10143 change h5PLget to use buffer like H5Iget_name

3 files changed, 74 insertions, 44 deletions

diff --git a/src/H5PL.c b/src/H5PL.c
index 4bf19fc..0957629 100644
--- a/src/H5PL.c
+++ b/src/H5PL.c
@@ -428,19 +428,15 @@ H5PLappend(const char* plugin_path)
     if(NULL == plugin_path)
         HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "no path provided")
     dl_path = H5MM_strdup(plugin_path);
-    if(NULL == dl_path)
+    if(NULL == (dl_path = H5MM_strdup(plugin_path)))
         HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "can't allocate memory for path")
 
     H5PL_EXPAND_ENV_VAR
 
     H5PL_path_table_g[H5PL_num_paths_g] = dl_path;
-    dl_path = NULL;
     H5PL_num_paths_g++;
 
 done:
-    if(dl_path)
-        dl_path = (char *)H5MM_xfree(dl_path);
-
     FUNC_LEAVE_API(ret_value)
 } /* end H5PLappend() */
 
@@ -466,8 +462,7 @@ H5PLprepend(const char* plugin_path)
         HGOTO_ERROR(H5E_PLUGIN, H5E_NOSPACE, FAIL, "too many directories in path for table")
     if(NULL == plugin_path)
         HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "no path provided")
-    dl_path = H5MM_strdup(plugin_path);
-    if(NULL == dl_path)
+    if(NULL == (dl_path = H5MM_strdup(plugin_path)))
         HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "can't allocate memory for path")
 
     H5PL_EXPAND_ENV_VAR
@@ -475,13 +470,9 @@ H5PLprepend(const char* plugin_path)
     for (plindex = (unsigned int)H5PL_num_paths_g; plindex > 0; plindex--)
         H5PL_path_table_g[plindex] = H5PL_path_table_g[plindex - 1];
     H5PL_path_table_g[0] = dl_path;
-    dl_path = NULL;
     H5PL_num_paths_g++;
 
 done:
-    if (dl_path)
-        dl_path = (char *)H5MM_xfree(dl_path);
-
     FUNC_LEAVE_API(ret_value)
 } /* end H5PLprepend() */
 
@@ -504,8 +495,7 @@ H5PLreplace(const char* plugin_path, unsigned int index)
     FUNC_ENTER_API(FAIL)
     if(NULL == plugin_path)
         HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "no path provided")
-    dl_path = H5MM_strdup(plugin_path);
-    if(NULL == dl_path)
+    if(NULL == (dl_path = H5MM_strdup(plugin_path)))
         HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "can't allocate memory for path")
 
     H5PL_EXPAND_ENV_VAR
@@ -513,12 +503,8 @@ H5PLreplace(const char* plugin_path, unsigned int index)
     if(H5PL_path_table_g[index])
         H5PL_path_table_g[index] = (char *)H5MM_xfree(H5PL_path_table_g[index]);
     H5PL_path_table_g[index] = dl_path;
-    dl_path = NULL;
 
 done:
-    if(dl_path)
-        dl_path = (char *)H5MM_xfree(dl_path);
-
     FUNC_LEAVE_API(ret_value)
 } /* end H5PLreplace() */
 
@@ -544,8 +530,7 @@ H5PLinsert(const char* plugin_path, unsigned int index)
         HGOTO_ERROR(H5E_PLUGIN, H5E_NOSPACE, FAIL, "too many directories in path for table")
     if(NULL == plugin_path)
         HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "no path provided")
-    dl_path = H5MM_strdup(plugin_path);
-    if(NULL == dl_path)
+    if(NULL == (dl_path = H5MM_strdup(plugin_path)))
         HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "can't allocate memory for path")
 
     H5PL_EXPAND_ENV_VAR
@@ -553,13 +538,9 @@ H5PLinsert(const char* plugin_path, unsigned int index)
     for(plindex = (unsigned int)H5PL_num_paths_g; plindex > index; plindex--)
         H5PL_path_table_g[plindex] = H5PL_path_table_g[plindex - 1];
     H5PL_path_table_g[index] = dl_path;
-    dl_path = NULL;
     H5PL_num_paths_g++;
 
 done:
-    if(dl_path)
-        dl_path = (char *)H5MM_xfree(dl_path);
-
     FUNC_LEAVE_API(ret_value)
 } /* end H5PLinsert() */
 
@@ -602,20 +583,40 @@ done:
  *
  * Purpose: Query the plugin path at the specified index.
  *
- * Return:      Non-NULL on success/NULL on failure
+ * Return: Success: The length of path.
+ *
+ *  If `pathname' is non-NULL then write up to `size' bytes into that
+ *  buffer and always return the length of the pathname.
+ *  Otherwise `size' is ignored and the function does not store the pathname,
+ *  just returning the number of characters required to store the pathname.
+ *  If an error occurs then the buffer pointed to by `pathname' (NULL or non-NULL)
+ *  is unchanged and the function returns a negative value.
+ *  If a zero is returned for the name's length, then there is no pathname
+ *  associated with the index.
  *
  *-------------------------------------------------------------------------
  */
-const char*
-H5PLget(unsigned int index)
+ssize_t
+H5PLget(unsigned int index, char *pathname/*out*/, size_t size)
 {
-    char* ret_value = NULL; /* Return value */
+    ssize_t      ret_value = FAIL;    /* Return value */
+    ssize_t      len = 0;      /* Length of pathname */
+    char        *dl_path = NULL;
 
-    FUNC_ENTER_API(NULL)
+    FUNC_ENTER_API(FAIL)
     if(H5PL_num_paths_g == 0)
-        HGOTO_ERROR(H5E_PLUGIN, H5E_NOSPACE, NULL, "no directories in table")
-    if(NULL == (ret_value = H5PL_path_table_g[index]))
-        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, NULL, "no directory path at index")
+        HGOTO_ERROR(H5E_PLUGIN, H5E_NOSPACE, FAIL, "no directories in table")
+    if(NULL == (dl_path = H5PL_path_table_g[index]))
+        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "no directory path at index")
+    len = HDstrlen(dl_path);
+    if(pathname) {
+        HDstrncpy(pathname, dl_path, MIN((size_t)(len + 1), size));
+        if((size_t)len >= size)
+            pathname[size - 1] = '\0';
+    } /* end if */
+
+    /* Set return value */
+    ret_value = len;
 
 done:
     FUNC_LEAVE_API(ret_value)
diff --git a/src/H5PLpublic.h b/src/H5PLpublic.h
index ca46542..5e4dcae 100644
--- a/src/H5PLpublic.h
+++ b/src/H5PLpublic.h
@@ -49,7 +49,7 @@ H5_DLL herr_t H5PLprepend(const char* plugin_path);
 H5_DLL herr_t H5PLreplace(const char* plugin_path, unsigned int index);
 H5_DLL herr_t H5PLinsert(const char* plugin_path, unsigned int index);
 H5_DLL herr_t H5PLremove(unsigned int index);
-H5_DLL const char* H5PLget(unsigned int index);
+H5_DLL ssize_t H5PLget(unsigned int index, char *pathname/*out*/, size_t size);
 H5_DLL unsigned int H5PLsize(void);
 
 #ifdef __cplusplus
diff --git a/test/plugin.c b/test/plugin.c
index 359bbdd..19a0ebd 100644
--- a/test/plugin.c
+++ b/test/plugin.c
@@ -744,6 +744,7 @@ test_filter_path_apis(void)
     int          i;
     unsigned int ndx;
     herr_t       ret;
+    int          pathlen = -1;
     char         pathname[256];
 
     HDputs("Testing access to the filter path table");
@@ -801,18 +802,37 @@ test_filter_path_apis(void)
         TEST_ERROR
     PASSED();
 
-    TESTING("    get (bounds)");
-    HDsprintf(pathname, "%s", H5PLget(0));
+    TESTING("    get (path name)");
+    if ((pathlen = H5PLget(0, NULL, 0)) <= 0) {
+        HDfprintf(stderr,"    get path 0 length failed\n");
+        TEST_ERROR
+    }
+    HDfprintf(stdout,"    get path 0 length %d\n", pathlen);
+    if (pathlen != 8) {
+        TEST_ERROR
+    }
+    if ((pathlen = H5PLget(0, pathname, 256)) <= 0) {
+        HDfprintf(stderr,"    get 0 len: %d : %s\n", pathlen, pathname);
+        TEST_ERROR
+    }
+    HDfprintf(stdout,"    get path 0 length %d\n", pathlen);
     if (strcmp(pathname, "a_path_0") != 0) {
         HDfprintf(stderr,"    get 0: %s\n", pathname);
         TEST_ERROR
     }
-    HDsprintf(pathname, "%s", H5PLget(1));
+    PASSED();
+
+    TESTING("    get (bounds)");
+    if ((pathlen = H5PLget(1, pathname, 256)) <= 0)
+        TEST_ERROR
+    HDfprintf(stdout,"    get path 1 length %d\n", pathlen);
     if (strcmp(pathname, "a_path_1") != 0) {
         HDfprintf(stderr,"    get 1: %s\n", pathname);
         TEST_ERROR
     }
-    HDsprintf(pathname, "%s", H5PLget(15));
+    if ((pathlen = H5PLget(15, pathname, 256)) <= 0)
+        TEST_ERROR
+    HDfprintf(stdout,"    get path 15 length %d\n", pathlen);
     if (strcmp(pathname, "a_path_15") != 0) {
         HDfprintf(stderr,"    get 15: %s\n", pathname);
         TEST_ERROR
@@ -820,16 +840,19 @@ test_filter_path_apis(void)
     PASSED();
 
     TESTING("    get (bounds exceed)");
-    if (H5PLget(16) != NULL)
+    if ((pathlen = H5PLget(16, NULL, 0)) > 0)
         TEST_ERROR
     PASSED();
+    HDfprintf(stdout,"    get path 16 length %d\n", pathlen);
 
     TESTING("    remove (verify for prepend)");
     /* Remove one path*/
     if (H5PLremove(8) < 0) TEST_ERROR
 
     /* Verify that the entries were moved */
-    HDsprintf(pathname, "%s", H5PLget(8));
+    if ((pathlen = H5PLget(8, pathname, 256)) <= 0)
+        TEST_ERROR
+    HDfprintf(stdout,"    get path 8 length %d\n", pathlen);
     if (strcmp(pathname, "a_path_9") != 0) {
         HDfprintf(stderr,"    get 8: %s\n", pathname);
         TEST_ERROR
@@ -851,12 +874,14 @@ test_filter_path_apis(void)
     if (H5PLsize() != 16) TEST_ERROR
 
     /* Verify that the entries were moved */
-    HDsprintf(pathname, "%s", H5PLget(8));
+    if (H5PLget(8, pathname, 256) <= 0)
+        TEST_ERROR
     if (strcmp(pathname, "a_path_7") != 0) {
         HDfprintf(stderr,"    get 8: %s\n", pathname);
         TEST_ERROR
     }
-    HDsprintf(pathname, "%s", H5PLget(0));
+    if (H5PLget(0, pathname, 256) <= 0)
+        TEST_ERROR
     if (strcmp(pathname, "a_path_17") != 0) {
         HDfprintf(stderr,"    get 0: %s\n", pathname);
         TEST_ERROR
@@ -885,12 +910,14 @@ test_filter_path_apis(void)
     if (H5PLsize() != 16) TEST_ERROR
 
     /* Verify that the entries were not moved */
-    HDsprintf(pathname, "%s", H5PLget(0));
+    if (H5PLget(0, pathname, 256) <= 0)
+        TEST_ERROR
     if (strcmp(pathname, "a_path_17") != 0) {
         HDfprintf(stderr,"    get 0: %s\n", pathname);
         TEST_ERROR
     }
-    HDsprintf(pathname, "%s", H5PLget(2));
+    if (H5PLget(2, pathname, 256) <= 0)
+        TEST_ERROR
     if (strcmp(pathname, "a_path_1") != 0) {
         HDfprintf(stderr,"    get 2: %s\n", pathname);
         TEST_ERROR
@@ -902,7 +929,8 @@ test_filter_path_apis(void)
     if (H5PLremove(4) < 0) TEST_ERROR
 
     /* Verify that the entries were moved */
-    HDsprintf(pathname, "%s", H5PLget(4));
+    if (H5PLget(4, pathname, 256) <= 0)
+        TEST_ERROR
     if (strcmp(pathname, "a_path_4") != 0) {
         HDfprintf(stderr,"    get 4: %s\n", pathname);
         TEST_ERROR
@@ -921,7 +949,8 @@ test_filter_path_apis(void)
     }
 
     /* Verify that the entries were moved */
-    HDsprintf(pathname, "%s", H5PLget(4));
+    if (H5PLget(4, pathname, 256) <= 0)
+        TEST_ERROR
     if (strcmp(pathname, "a_path_2") != 0){
         HDfprintf(stderr,"    get 4: %s\n", pathname);
         TEST_ERROR