Add pdfioDictGetKey and pdfioDictGetNumPairs APIs (Issue #63)

Add pdfioArrayRemove and pdfioDictClear APIs (Issue #74)

CHANGES.md

@@ -5,6 +5,8 @@ Changes in PDFio
 v1.4.0 - YYYY-MM-DD
 -------------------
 
+- Added new `pdfioDictGetKey` and `pdfioDictGetNumPairs` APIs (Issue #63)
+- Added new `pdfioArrayRemove` and `pdfioDictClear` APIs (Issue #74)
 - Added new `pdfioFileCreateNameObj` and `pdfioObjGetName` APIs for creating and
   getting name object values (Issue #76)
 - Updated documentation (Issue #78)

pdfio-array.c

@@ -1,7 +1,7 @@
 //
 // PDF array functions for PDFio.
 //
-// Copyright © 2021 by Michael R Sweet.
+// Copyright © 2021-2024 by Michael R Sweet.
 //
 // Licensed under Apache License v2.0.  See the file "LICENSE" for more
 // information.
@@ -637,6 +637,28 @@ _pdfioArrayRead(pdfio_file_t   *pdf,	// I - PDF file
 }
 
 
+//
+// 'pdfioArrayRemove()' - Remove an array entry.
+//
+
+bool					// O - `true` on success, `false` otherwise
+pdfioArrayRemove(pdfio_array_t *a,	// I - Array
+                 size_t        n)	// I - Index
+{
+  if (!a || n >= a->num_values)
+    return (false);
+
+  if (a->values[n].type == PDFIO_VALTYPE_BINARY)
+    free(a->values[n].value.binary.data);
+
+  a->num_values --;
+  if (n < a->num_values)
+    memmove(a->values + n, a->values + n + 1, (a->num_values - n) * sizeof(_pdfio_value_t));
+
+  return (true);
+}
+
+
 //
 // '_pdfioArrayWrite()' - Write an array to a PDF file.
 //

pdfio-dict.c

@@ -1,7 +1,7 @@
 //
 // PDF dictionary functions for PDFio.
 //
-// Copyright © 2021-2023 by Michael R Sweet.
+// Copyright © 2021-2024 by Michael R Sweet.
 //
 // Licensed under Apache License v2.0.  See the file "LICENSE" for more
 // information.
@@ -18,19 +18,22 @@ static int	compare_pairs(_pdfio_pair_t *a, _pdfio_pair_t *b);
 
 
 //
-// '_pdfioDictClear()' - Remove a key/value pair from a dictionary.
+// 'pdfioDictClear()' - Remove a key/value pair from a dictionary.
 //
 
-void
-_pdfioDictClear(pdfio_dict_t *dict,	// I - Dictionary
-                const char   *key)	// I - Key
+bool					// O - `true` if cleared, `false` otherwise
+pdfioDictClear(pdfio_dict_t *dict,	// I - Dictionary
+               const char   *key)	// I - Key
 {
   size_t	idx;			// Index into pairs
   _pdfio_pair_t	*pair,			// Current pair
 		pkey;			// Search key
 
 
-  PDFIO_DEBUG("_pdfioDictClear(dict=%p, key=\"%s\")\n", dict, key);
+  PDFIO_DEBUG("pdfioDictClear(dict=%p, key=\"%s\")\n", dict, key);
+
+  if (!dict || !key)
+    return (false);
 
   // See if the key is already set...
   if (dict->num_pairs > 0)
@@ -48,8 +51,12 @@ _pdfioDictClear(pdfio_dict_t *dict,	// I - Dictionary
 
       if (idx < dict->num_pairs)
         memmove(pair, pair + 1, (dict->num_pairs - idx) * sizeof(_pdfio_pair_t));
+
+      return (true);
     }
   }
+
+  return (false);
 }
 
 
@@ -335,6 +342,18 @@ pdfioDictGetDict(pdfio_dict_t *dict,	// I - Dictionary
 }
 
 
+//
+// 'pdfioDictGetKey()' - Get the key for the specified pair.
+//
+
+const char *				// O - Key for specified pair
+pdfioDictGetKey(pdfio_dict_t *dict,	// I - Dictionary
+                size_t       n)		// I - Pair index (`0`-based)
+{
+  return ((dict && n < dict->num_pairs) ? dict->pairs[n].key : NULL);
+}
+
+
 //
 // 'pdfioDictGetName()' - Get a key name value from a dictionary.
 //
@@ -353,6 +372,17 @@ pdfioDictGetName(pdfio_dict_t *dict,	// I - Dictionary
 }
 
 
+//
+// 'pdfioDictGetNumPairs()' - Get the number of key/value pairs in a dictionary.
+//
+
+size_t					// O - Number of pairs
+pdfioDictGetNumPairs(pdfio_dict_t *dict)// I - Dictionary
+{
+  return (dict ? dict->num_pairs : 0);
+}
+
+
 //
 // 'pdfioDictGetNumber()' - Get a key number value from a dictionary.
 //

pdfio-object.c

@@ -99,7 +99,7 @@ pdfioObjCopy(pdfio_file_t *pdf,		// I - PDF file
     return (NULL);
 
   if (dstobj->value.type == PDFIO_VALTYPE_DICT)
-    _pdfioDictClear(dstobj->value.value.dict, "Length");
+    pdfioDictClear(dstobj->value.value.dict, "Length");
 
   if (srcobj->stream_offset)
   {

pdfio-private.h

@@ -353,7 +353,6 @@ extern void		_pdfioCryptoSHA256Init(_pdfio_sha256_t *ctx) _PDFIO_INTERNAL;
 extern void		_pdfioCryptoSHA256Finish(_pdfio_sha256_t *ctx, uint8_t *Message_Digest) _PDFIO_INTERNAL;
 extern bool		_pdfioCryptoUnlock(pdfio_file_t *pdf, pdfio_password_cb_t password_cb, void *password_data) _PDFIO_INTERNAL;
 
-extern void		_pdfioDictClear(pdfio_dict_t *dict, const char *key) _PDFIO_INTERNAL;
 extern bool		_pdfioDictDecrypt(pdfio_file_t *pdf, pdfio_obj_t *obj, pdfio_dict_t *dict, size_t depth) _PDFIO_INTERNAL;
 extern void		_pdfioDictDebug(pdfio_dict_t *dict, FILE *fp) _PDFIO_INTERNAL;
 extern void		_pdfioDictDelete(pdfio_dict_t *dict) _PDFIO_INTERNAL;

pdfio.h

@@ -151,7 +151,9 @@ extern pdfio_obj_t	*pdfioArrayGetObj(pdfio_array_t *a, size_t n) _PDFIO_PUBLIC;
 extern size_t		pdfioArrayGetSize(pdfio_array_t *a) _PDFIO_PUBLIC;
 extern const char	*pdfioArrayGetString(pdfio_array_t *a, size_t n) _PDFIO_PUBLIC;
 extern pdfio_valtype_t	pdfioArrayGetType(pdfio_array_t *a, size_t n) _PDFIO_PUBLIC;
+extern bool		pdfioArrayRemove(pdfio_array_t *a, size_t n) _PDFIO_PUBLIC;
 
+extern bool		pdfioDictClear(pdfio_dict_t *dict, const char *key) _PDFIO_PUBLIC;
 extern pdfio_dict_t	*pdfioDictCopy(pdfio_file_t *pdf, pdfio_dict_t *dict) _PDFIO_PUBLIC;
 extern pdfio_dict_t	*pdfioDictCreate(pdfio_file_t *pdf) _PDFIO_PUBLIC;
 extern pdfio_array_t	*pdfioDictGetArray(pdfio_dict_t *dict, const char *key) _PDFIO_PUBLIC;
@@ -159,7 +161,9 @@ extern unsigned char	*pdfioDictGetBinary(pdfio_dict_t *dict, const char *key, si
 extern bool		pdfioDictGetBoolean(pdfio_dict_t *dict, const char *key) _PDFIO_PUBLIC;
 extern time_t		pdfioDictGetDate(pdfio_dict_t *dict, const char *key) _PDFIO_PUBLIC;
 extern pdfio_dict_t	*pdfioDictGetDict(pdfio_dict_t *dict, const char *key) _PDFIO_PUBLIC;
+extern const char	*pdfioDictGetKey(pdfio_dict_t *dict, size_t n) _PDFIO_PUBLIC;
 extern const char	*pdfioDictGetName(pdfio_dict_t *dict, const char *key) _PDFIO_PUBLIC;
+extern size_t		pdfioDictGetNumPairs(pdfio_dict_t *dict) _PDFIO_PUBLIC;
 extern double		pdfioDictGetNumber(pdfio_dict_t *dict, const char *key) _PDFIO_PUBLIC;
 extern pdfio_obj_t	*pdfioDictGetObj(pdfio_dict_t *dict, const char *key) _PDFIO_PUBLIC;
 extern pdfio_rect_t	*pdfioDictGetRect(pdfio_dict_t *dict, const char *key, pdfio_rect_t *rect) _PDFIO_PUBLIC;