string: Overhaul para_strdup().

[paraslash.git] / string.c

diff --git a/string.c b/string.c
index e675502cf6707240a61be523c6fb510692991acd..cc6dc2e26227c59bdb04715dfb8b031f1a11e5d9 100644 (file)
--- a/string.c
+++ b/string.c
@@ -1,8 +1,4 @@
-/*
- * Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
 /** \file string.c Memory allocation and string handling functions. */
 
@@ -98,28 +94,29 @@ __must_check __malloc void *para_calloc(size_t size)
  *
  * \param s The string to be duplicated.
  *
- * A wrapper for strdup(3). It calls \p exit(EXIT_FAILURE) on errors, i.e.
- * there is no need to check the return value in the caller.
+ * A strdup(3)-like function which aborts if insufficient memory was available
+ * to allocate the duplicated string, absolving the caller from the
+ * responsibility to check for failure.
  *
- * \return A pointer to the duplicated string. If \a s was the \p NULL pointer,
- * an pointer to an empty string is returned.
+ * \return A pointer to the duplicated string. Unlike strdup(3), the caller may
+ * pass NULL, in which case the function returns a pointer to an empty string.
+ * Regardless of whether or not NULL was passed, the returned string is
+ * allocated on the heap and has to be freed by the caller.
  *
- * \sa strdup(3)
+ * \sa strdup(3).
  */
 __must_check __malloc char *para_strdup(const char *s)
 {
-       char *ret;
+       char *dupped_string = strdup(s? s: "");
 
-       if ((ret = strdup(s? s: "")))
-               return ret;
-       PARA_EMERG_LOG("strdup failed, aborting\n");
-       exit(EXIT_FAILURE);
+       assert(dupped_string);
+       return dupped_string;
 }
 
 /**
- * Print a formated message to a dynamically allocated string.
+ * Print a formatted message to a dynamically allocated string.
  *
- * \param result The formated string is returned here.
+ * \param result The formatted string is returned here.
  * \param fmt The format string.
  * \param ap Initialized list of arguments.
  *
@@ -203,17 +200,22 @@ __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
 }
 
 /**
- * Free the content of a pointer and set it to \p NULL.
+ * Free the content of a pointer and set it to NULL.
  *
- * This is equivalent to "free(*arg); *arg = NULL;".
+ * \param arg A pointer to the pointer whose content should be freed.
  *
- * \param arg The pointer whose content should be freed.
+ * If arg is NULL, the function returns immediately. Otherwise it frees the
+ * memory pointed to by *arg and sets *arg to NULL. Hence callers have to pass
+ * the *address* of the pointer variable that points to the memory which should
+ * be freed.
  */
 void freep(void *arg)
 {
-       void **ptr = (void **)arg;
-       free(*ptr);
-       *ptr = NULL;
+       if (arg) {
+               void **ptr = arg;
+               free(*ptr);
+               *ptr = NULL;
+       }
 }
 
 /**
@@ -244,56 +246,6 @@ __must_check __malloc char *para_strcat(char *a, const char *b)
        return tmp;
 }
 
-/**
- * Paraslash's version of dirname().
- *
- * \param name Pointer to the full path.
- *
- * Compute the directory component of \p name.
- *
- * \return If \a name is \p NULL or the empty string, return \p NULL.
- * Otherwise, Make a copy of \a name and return its directory component. Caller
- * is responsible to free the result.
- */
-__must_check __malloc char *para_dirname(const char *name)
-{
-       char *p, *ret;
-
-       if (!name || !*name)
-               return NULL;
-       ret = para_strdup(name);
-       p = strrchr(ret, '/');
-       if (!p)
-               *ret = '\0';
-       else
-               *p = '\0';
-       return ret;
-}
-
-/**
- * Paraslash's version of basename().
- *
- * \param name Pointer to the full path.
- *
- * Compute the filename component of \a name.
- *
- * \return \p NULL if (a) \a name is the empty string or \p NULL, or (b) name
- * ends with a slash.  Otherwise, a pointer within \a name is returned.  Caller
- * must not free the result.
- */
-__must_check char *para_basename(const char *name)
-{
-       char *ret;
-
-       if (!name || !*name)
-               return NULL;
-       ret = strrchr(name, '/');
-       if (!ret)
-               return (char *)name;
-       ret++;
-       return ret;
-}
-
 /**
  * Get the logname of the current user.
  *