bk commit into 5.0 tree (jani:1.1963) BUG#10806

[jani]

Below is the list of changes that have just been committed into a local
5.0 repository of jani. When jani does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
For information on how to access the public repository
see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet
  1.1963 05/06/09 21:50:22 jani@stripped +1 -0
  Fixes in function modify_defaults_file():
  
  - Removed unneccessary variables.
  - Made a function of that part of code, which actually changes 
    the line under modifications.
  - Fixed memory overrun problem with my_malloc. Too little space
    was reserved.
  - Fixed problem in case, when new option was added at the end
    of the section. Before, it was added as the last line of the
    section, even if it left empty lines between.
  - Fixed so that the configuration file is not saved unneccessarily,
    if no modifications are done. (file timestamp remains)
  - This should fix (at least partially) problems described in
    Bug#10806

  mysys/default_modify.c
    1.4 05/06/09 21:50:09 jani@stripped +69 -46
    Fixes in function modify_defaults_file():
    
    - Removed unneccessary variables.
    - Made a function of that part of code, which actually changes 
      the line under modifications.
    - Fixed memory overrun problem with my_malloc. Too little space
      was reserved.
    - Fixed problem in case, when new option was added at the end
      of the section. Before, it was added as the last line of the
      section, even if it left empty lines between.
    - Fixed so that the configuration file is not saved unneccessarily,
      if no modifications are done. (file timestamp remains)
    - This should fix (at least partially) problems described in
      Bug#10806

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	jani
# Host:	a193-229-222-105.elisa-laajakaista.fi
# Root:	/home/my/bk/mysql-5.0

--- 1.3/mysys/default_modify.c	2005-05-22 00:22:12 +03:00
+++ 1.4/mysys/default_modify.c	2005-06-09 21:50:09 +03:00
@@ -37,22 +37,20 @@
 #define NEWLINE_LEN 1
 #endif
 
+static char *add_option(char *dst, const char *option_value,
+			const char *option, int remove_option);
+
 int modify_defaults_file(const char *file_location, const char *option,
                          const char *option_value,
                          const char *section_name, int remove_option)
 {
   FILE *cnf_file;
   MY_STAT file_stat;
-  char linebuff[BUFF_SIZE], tmp[BUFF_SIZE], *tmp_ptr, *src_ptr, *dst_ptr,
-       *file_buffer;
-  uint optlen, optval_len, sect_len;
-  my_bool in_section= FALSE;
+  char linebuff[BUFF_SIZE], *src_ptr, *dst_ptr, *file_buffer;
+  uint optlen, optval_len, sect_len, nr_newlines= 0;
+  my_bool in_section= FALSE, opt_applied= 0;
   DBUG_ENTER("modify_defaults_file");
 
-  optlen= strlen(option);
-  optval_len= strlen(option_value);
-  sect_len= strlen(section_name);
-
   if (!(cnf_file= my_fopen(file_location, O_RDWR | O_BINARY, MYF(0))))
     DBUG_RETURN(2);
 
@@ -60,12 +58,15 @@
   if (my_fstat(fileno(cnf_file), &file_stat, MYF(0)))
     goto err;
 
+  optlen= strlen(option);
+  optval_len= strlen(option_value);
+
   /*
     Reserve space to read the contents of the file and some more
     for the option we want to add.
   */
-  if (!(file_buffer= (char*) my_malloc(sizeof(char)*
-				       (file_stat.st_size +
+  if (!(file_buffer= (char*) my_malloc(sizeof(char) *
+				       (file_stat.st_size + 
 					/* option name len */
 					optlen +
 					/* reserve space for newline */
@@ -73,35 +74,44 @@
 					/* reserve for '=' char */
 					1 +           
 					/* option value len */
-					optval_len), MYF(MY_WME))))
+					optval_len +
+					/* The ending zero plus some safety */
+					FN_REFLEN), MYF(MY_WME))))
     goto malloc_err;
 
-  for (dst_ptr= file_buffer, tmp_ptr= 0;
-       fgets(linebuff, BUFF_SIZE, cnf_file); )
+  sect_len= strlen(section_name);
+
+  for (dst_ptr= file_buffer; fgets(linebuff, BUFF_SIZE, cnf_file); )
   {
     /* Skip over whitespaces */
     for (src_ptr= linebuff; my_isspace(&my_charset_latin1, *src_ptr);
 	 src_ptr++)
     {}
 
-    if (in_section && !strncmp(src_ptr, option, optlen) &&
+    if (!*src_ptr) /* Empty line */
+    {
+      nr_newlines++;
+      continue;
+    }
+
+    if (!opt_applied && in_section && !strncmp(src_ptr, option, optlen) &&
 	(*(src_ptr + optlen) == '=' ||
 	 my_isspace(&my_charset_latin1, *(src_ptr + optlen)) ||
 	 *(src_ptr + optlen) == '\0'))
     {
-      /* The option under modifying was found in this section. Apply new. */
-      if (!remove_option)
-	dst_ptr= strmov(dst_ptr, tmp);
-      tmp_ptr= 0; /* To mark that we have already applied this */
+      dst_ptr= add_option(dst_ptr, option_value, option, remove_option);
+      opt_applied= 1;
     }
     else
     {
       /* If going to new group and we have option to apply, do it now */
-      if (tmp_ptr && *src_ptr == '[')
+      if (in_section && !opt_applied && *src_ptr == '[')
       {
-	dst_ptr= strmov(dst_ptr, tmp);
-	tmp_ptr= 0;
+	dst_ptr= add_option(dst_ptr, option_value, option, remove_option);
+
       }
+      for (; nr_newlines; nr_newlines--)
+	dst_ptr= strmov(dst_ptr, NEWLINE);	
       dst_ptr= strmov(dst_ptr, linebuff);
     }
     /* Look for a section */
@@ -117,43 +127,38 @@
 
 	if (*src_ptr != ']')
 	  continue; /* Missing closing parenthesis. Assume this was no group */
-	
         in_section= TRUE;
-        /* add option */
-        if (!remove_option)
-        {
-          tmp_ptr= strmov(tmp, option);
-          if (*option_value)
-          {
-	    *tmp_ptr++= '=';
-            tmp_ptr= strmov(tmp_ptr, option_value);
-          }
-          /* add a newline */
-	  strmov(tmp_ptr, NEWLINE);
-        }
       }
       else
         in_section= FALSE; /* mark that this section is of no interest to us */
     }
   }
-  /* File ended. New option still remains to apply at the end */
-  if (tmp_ptr)
+  /* File ended. */
+  if (!opt_applied && !remove_option && in_section)
   {
+    /* New option still remains to apply at the end */
     if (*(dst_ptr - 1) != '\n')
-      *dst_ptr++= '\n';
-    dst_ptr= strmov(dst_ptr, tmp);    
+      dst_ptr= strmov(dst_ptr, NEWLINE);
+    dst_ptr= add_option(dst_ptr, option_value, option, remove_option);
+    opt_applied= 1;
   }
+  for (; nr_newlines; nr_newlines--)
+    dst_ptr= strmov(dst_ptr, NEWLINE);
 
-  if (my_chsize(fileno(cnf_file), (my_off_t) (dst_ptr - file_buffer), 0,
-		MYF(MY_WME)) ||
-      my_fseek(cnf_file, 0, MY_SEEK_SET, MYF(0)) ||
-      my_fwrite(cnf_file, file_buffer, (uint) (dst_ptr - file_buffer),
-		MYF(MY_NABP)) ||
-      my_fclose(cnf_file, MYF(MY_WME)))
-     goto err;
+  if (opt_applied)
+  {
+    /* Don't write the file if there are no changes to be made */
+    if (my_chsize(fileno(cnf_file), (my_off_t) (dst_ptr - file_buffer), 0,
+		  MYF(MY_WME)) ||
+	my_fseek(cnf_file, 0, MY_SEEK_SET, MYF(0)) ||
+	my_fwrite(cnf_file, file_buffer, (uint) (dst_ptr - file_buffer),
+		  MYF(MY_NABP)))
+      goto err;
+  }
+  if (my_fclose(cnf_file, MYF(MY_WME)))
+    goto err;
 
   my_free(file_buffer, MYF(0));
-
   DBUG_RETURN(0);
 
 err:
@@ -161,4 +166,22 @@
 malloc_err:
   my_fclose(cnf_file, MYF(0));
   DBUG_RETURN(1); /* out of resources */
+}
+
+
+static char *add_option(char *dst, const char *option_value,
+			const char *option, int remove_option)
+{
+  if (!remove_option)
+  {
+    dst= strmov(dst, option);
+    if (*option_value)
+    {
+      *dst++= '=';
+      dst= strmov(dst, option_value);
+    }
+    /* add a newline */
+    dst= strmov(dst, NEWLINE);
+  }
+  return dst;
 }