Functions to work with null delimited lists.

copy_double_null() duplicates a null delimited list.

append_to_double_null() adds an entry to a list, or replaces an entry
which matches a given substring of the new value.

remove_from_double_null() removes an entry from a list, possibly only if
it matches a given substring.

diff --git a/registry.cpp b/registry.cpp
index 4e432ab..c78cb8c 100644 (file)
--- a/registry.cpp
+++ b/registry.cpp
@@ -260,8 +260,11 @@ int get_environment(TCHAR *service_name, HKEY key, TCHAR *value, TCHAR **env, un
     return 2;\r
   }\r
 \r
-  /* Probably not possible */\r
-  if (! envsize) return 0;\r
+  /* Minimum usable environment would be A= NULL NULL. */\r
+  if (envsize < 4 * sizeof(TCHAR)) {\r
+    *env = 0;\r
+    return 3;\r
+  }\r
 \r
   /* Previously initialised? */\r
   if (*env) HeapFree(GetProcessHeap(), 0, *env);\r
@@ -269,7 +272,7 @@ int get_environment(TCHAR *service_name, HKEY key, TCHAR *value, TCHAR **env, un
   *env = (TCHAR *) HeapAlloc(GetProcessHeap(), 0, envsize);\r
   if (! *env) {\r
     log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, value, _T("get_environment()"), 0);\r
-    return 3;\r
+    return 4;\r
   }\r
 \r
   /* Actually get the strings. */\r
@@ -278,11 +281,11 @@ int get_environment(TCHAR *service_name, HKEY key, TCHAR *value, TCHAR **env, un
     log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_QUERYVALUE_FAILED, value, error_string(ret), 0);\r
     HeapFree(GetProcessHeap(), 0, *env);\r
     *env = 0;\r
-    return 4;\r
+    return 5;\r
   }\r
 \r
   /* Value retrieved by RegQueryValueEx() is SIZE not COUNT. */\r
-  *envlen = (unsigned long) environment_length(env);\r
+  *envlen = (unsigned long) environment_length(*env);\r
 \r
   return 0;\r
 }\r
@@ -497,6 +500,153 @@ int unformat_double_null(TCHAR *formatted, unsigned long formattedlen, TCHAR **d
   return 0;\r
 }\r
 \r
+/* Copy a block. */\r
+int copy_double_null(TCHAR *dn, unsigned long dnlen, TCHAR **newdn) {\r
+  if (! newdn) return 1;\r
+\r
+  *newdn = 0;\r
+  if (! dn) return 0;\r
+\r
+  *newdn = (TCHAR *) HeapAlloc(GetProcessHeap(), 0, dnlen * sizeof(TCHAR));\r
+  if (! *newdn) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, _T("dn"), _T("copy_double_null()"), 0);\r
+    return 2;\r
+  }\r
+\r
+  memmove(*newdn, dn, dnlen * sizeof(TCHAR));\r
+  return 0;\r
+}\r
+\r
+/*\r
+  Create a new block with all the strings of the first block plus a new string.\r
+  The new string may be specified as <key> <delimiter> <value> and the keylen\r
+  gives the offset into the string to compare against existing entries.\r
+  If the key is already present its value will be overwritten in place.\r
+  If the key is blank or empty the new block will still be allocated and have\r
+  non-zero length.\r
+*/\r
+int append_to_double_null(TCHAR *dn, unsigned long dnlen, TCHAR **newdn, unsigned long *newlen, TCHAR *append, size_t keylen, bool case_sensitive) {\r
+  if (! append || ! append[0]) return copy_double_null(dn, dnlen, newdn);\r
+  size_t appendlen = _tcslen(append);\r
+  int (*fn)(const TCHAR *, const TCHAR *, size_t) = (case_sensitive) ? _tcsncmp : _tcsnicmp;\r
+\r
+  /* Identify the key, if any, or treat the whole string as the key. */\r
+  TCHAR *key = 0;\r
+  if (! keylen || keylen > appendlen) keylen = appendlen;\r
+  key = (TCHAR *) HeapAlloc(GetProcessHeap(), 0, (keylen + 1) * sizeof(TCHAR));\r
+  if (! key) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, _T("key"), _T("append_to_double_null()"), 0);\r
+    return 1;\r
+  }\r
+  memmove(key, append, keylen * sizeof(TCHAR));\r
+  key[keylen] = _T('\0');\r
+\r
+  /* Find the length of the block not including any existing key. */\r
+  size_t len = 0;\r
+  TCHAR *s;\r
+  for (s = dn; *s; s++) {\r
+    if (fn(s, key, keylen)) len += _tcslen(s) + 1;\r
+    for ( ; *s; s++);\r
+  }\r
+\r
+  /* Account for new entry. */\r
+  len += _tcslen(append) + 1;\r
+\r
+  /* Account for trailing NULL. */\r
+  len++;\r
+\r
+  /* Allocate a new block. */\r
+  *newdn = (TCHAR *) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, len * sizeof(TCHAR));\r
+  if (! *newdn) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, _T("newdn"), _T("append_to_double_null()"), 0);\r
+    HeapFree(GetProcessHeap(), 0, key);\r
+    return 2;\r
+  }\r
+\r
+  /* Copy existing entries.*/\r
+  *newlen = (unsigned long) len;\r
+  TCHAR *t = *newdn;\r
+  TCHAR *u;\r
+  bool replaced = false;\r
+  for (s = dn; *s; s++) {\r
+    if (fn(s, key, keylen)) u = s;\r
+    else {\r
+      u = append;\r
+      replaced = true;\r
+    }\r
+    len = _tcslen(u) + 1;\r
+    memmove(t, u, len * sizeof(TCHAR));\r
+    t += len;\r
+    for ( ; *s; s++);\r
+  }\r
+\r
+  /* Add the entry if it wasn't already replaced.  The buffer was zeroed. */\r
+  if (! replaced) memmove(t, append, _tcslen(append) * sizeof(TCHAR));\r
+\r
+  HeapFree(GetProcessHeap(), 0, key);\r
+  return 0;\r
+}\r
+\r
+/*\r
+  Create a new block with all the string of the first block minus the given\r
+  string.\r
+  The keylen parameter gives the offset into the string to compare against\r
+  existing entries.  If a substring of existing value matches the string to\r
+  the given length it will be removed.\r
+  If the last entry is removed the new block will still be allocated and\r
+  have non-zero length.\r
+*/\r
+int remove_from_double_null(TCHAR *dn, unsigned long dnlen, TCHAR **newdn, unsigned long *newlen, TCHAR *remove, size_t keylen, bool case_sensitive) {\r
+  if (! remove || !remove[0]) return copy_double_null(dn, dnlen, newdn);\r
+  size_t removelen = _tcslen(remove);\r
+  int (*fn)(const TCHAR *, const TCHAR *, size_t) = (case_sensitive) ? _tcsncmp : _tcsnicmp;\r
+\r
+  /* Identify the key, if any, or treat the whole string as the key. */\r
+  TCHAR *key = 0;\r
+  if (! keylen || keylen > removelen) keylen = removelen;\r
+  key = (TCHAR *) HeapAlloc(GetProcessHeap(), 0, (keylen + 1) * sizeof(TCHAR));\r
+  if (! key) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, _T("key"), _T("remove_from_double_null()"), 0);\r
+    return 1;\r
+  }\r
+  memmove(key, remove, keylen * sizeof(TCHAR));\r
+  key[keylen] = _T('\0');\r
+\r
+  /* Find the length of the block not including any existing key. */\r
+  size_t len = 0;\r
+  TCHAR *s;\r
+  for (s = dn; *s; s++) {\r
+    if (fn(s, key, keylen)) len += _tcslen(s) + 1;\r
+    for ( ; *s; s++);\r
+  }\r
+\r
+  /* Account for trailing NULL. */\r
+  if (++len < 2) len = 2;\r
+\r
+  /* Allocate a new block. */\r
+  *newdn = (TCHAR *) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, len * sizeof(TCHAR));\r
+  if (! *newdn) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, _T("newdn"), _T("remove_from_double_null()"), 0);\r
+    HeapFree(GetProcessHeap(), 0, key);\r
+    return 2;\r
+  }\r
+\r
+  /* Copy existing entries.*/\r
+  *newlen = (unsigned long) len;\r
+  TCHAR *t = *newdn;\r
+  for (s = dn; *s; s++) {\r
+    if (fn(s, key, keylen)) {\r
+      len = _tcslen(s) + 1;\r
+      memmove(t, s, len * sizeof(TCHAR));\r
+      t += len;\r
+    }\r
+    for ( ; *s; s++);\r
+  }\r
+\r
+  HeapFree(GetProcessHeap(), 0, key);\r
+  return 0;\r
+}\r
+\r
 void override_milliseconds(TCHAR *service_name, HKEY key, TCHAR *value, unsigned long *buffer, unsigned long default_value, unsigned long event) {\r
   unsigned long type = REG_DWORD;\r
   unsigned long buflen = sizeof(unsigned long);\r

diff --git a/registry.h b/registry.h
index 11c4e69..ad7cd7a 100644 (file)
--- a/registry.h
+++ b/registry.h
@@ -60,6 +60,9 @@ int get_number(HKEY, TCHAR *, unsigned long *, bool);
 int get_number(HKEY, TCHAR *, unsigned long *);\r
 int format_double_null(TCHAR *, unsigned long, TCHAR **, unsigned long *);\r
 int unformat_double_null(TCHAR *, unsigned long, TCHAR **, unsigned long *);\r
+int copy_double_null(TCHAR *, unsigned long, TCHAR **);\r
+int append_to_double_null(TCHAR *, unsigned long, TCHAR **, unsigned long *, TCHAR *, size_t, bool);\r
+int remove_from_double_null(TCHAR *, unsigned long, TCHAR **, unsigned long *, TCHAR *, size_t, bool);\r
 void override_milliseconds(TCHAR *, HKEY, TCHAR *, unsigned long *, unsigned long, unsigned long);\r
 int get_io_parameters(nssm_service_t *, HKEY);\r
 int get_parameters(nssm_service_t *, STARTUPINFO *);\r