[Findutils-patches] [PATCH 7/7] Fix some constness warnings when dealing with -printf formats.

[James Youngman]

* find/parser.c (collect_arg_nonconst): Rename collect_arg to
collect_arg_nonconst and change the collected argument from const
char* to char*.
(collect_arg): Call collect_arg_nonconst to do the real work.
(parse_printf): Call collect_arg_nonconst instead of collect_arg.
Change `format' from const char* to char*.
(parse_fprintf): Likewise.
* find/print.h: Change 'format' from const char* to char*, since
actually we edit it in place.
* find/print.c (parse_octal_escape): Instead of updating a const
char* pointer to indicate how many characters from the input we
consumed, update a size_t value.
(insert_fprintf): Change function defintion to match updated
prototype.  Eliminate fmt_inpos.  Introduce a `readpos' offset
variable which takes the previous role of fmt_inpos.
---
 ChangeLog     |   19 +++++++++++++++
 find/parser.c |   22 +++++++++++++----
 find/print.c  |   72 +++++++++++++++++++++++++++------------------------------
 find/print.h  |    2 +-
 4 files changed, 71 insertions(+), 44 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 2e477d3..412d219 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,22 @@
+2011-06-29  James Youngman  <address@hidden>
+
+       Fix some constness warnings when dealing with -printf formats.
+       * find/parser.c (collect_arg_nonconst): Rename collect_arg to
+       collect_arg_nonconst and change the collected argument from const
+       char* to char*.
+       (collect_arg): Call collect_arg_nonconst to do the real work.
+       (parse_printf): Call collect_arg_nonconst instead of collect_arg.
+       Change `format' from const char* to char*.
+       (parse_fprintf): Likewise.
+       * find/print.h: Change 'format' from const char* to char*, since
+       actually we edit it in place.
+       * find/print.c (parse_octal_escape): Instead of updating a const
+       char* pointer to indicate how many characters from the input we
+       consumed, update a size_t value.
+       (insert_fprintf): Change function defintion to match updated
+       prototype.  Eliminate fmt_inpos.  Introduce a `readpos' offset
+       variable which takes the previous role of fmt_inpos.
+
 2011-06-28  James Youngman  <address@hidden>
 
        Refactor insert_fprintf to minimise calls to make_segment.
diff --git a/find/parser.c b/find/parser.c
index 184e4e6..aa01253 100644
--- a/find/parser.c
+++ b/find/parser.c
@@ -694,7 +694,7 @@ estimate_timestamp_success_rate (time_t when)
  * return false.
  */
 static bool
-collect_arg (char **argv, int *arg_ptr, const char **collected_arg)
+collect_arg_nonconst (char **argv, int *arg_ptr, char **collected_arg)
 {
   if ((argv == NULL) || (argv[*arg_ptr] == NULL))
     {
@@ -710,6 +710,17 @@ collect_arg (char **argv, int *arg_ptr, const char 
**collected_arg)
 }
 
 static bool
+collect_arg (char **argv, int *arg_ptr, const char **collected_arg)
+{
+  char *arg;
+  const bool result = collect_arg_nonconst (argv, arg_ptr, &arg);
+  *collected_arg = arg;
+  return result;
+}
+
+
+
+static bool
 collect_arg_stat_info (char **argv, int *arg_ptr, struct stat *p,
                       const char **argument)
 {
@@ -2111,10 +2122,10 @@ parse_print0 (const struct parser_table* entry, char 
**argv, int *arg_ptr)
 static bool
 parse_printf (const struct parser_table* entry, char **argv, int *arg_ptr)
 {
-  const char *format;
+  char *format;
   const int saved_argc = *arg_ptr;
 
-  if (collect_arg (argv, arg_ptr, &format))
+  if (collect_arg_nonconst (argv, arg_ptr, &format))
     {
       struct format_val fmt;
       open_stdout (&fmt);
@@ -2134,12 +2145,13 @@ parse_printf (const struct parser_table* entry, char 
**argv, int *arg_ptr)
 static bool
 parse_fprintf (const struct parser_table* entry, char **argv, int *arg_ptr)
 {
-  const char *format, *filename;
+  const char *filename;
+  char *format;
   int saved_argc = *arg_ptr;
 
   if (collect_arg (argv, arg_ptr, &filename))
     {
-      if (collect_arg (argv, arg_ptr, &format))
+      if (collect_arg_nonconst (argv, arg_ptr, &format))
        {
          struct format_val fmt;
          open_output_file (filename, &fmt);
diff --git a/find/print.c b/find/print.c
index 862be43..e307d95 100644
--- a/find/print.c
+++ b/find/print.c
@@ -223,17 +223,17 @@ is_octal_char (char ch)
 }
 
 static char
-parse_octal_escape(const char **in)
+parse_octal_escape(const char *p, size_t *consumed)
 {
   register int n, i;
-  const char *p = (*in);
+  size_t pos = 0;
 
-  for (i = n = 0; i < 3 && is_octal_char(*p); i++, p++)
+  for (i = n = 0; i < 3 && is_octal_char(p[pos]); i++, pos++)
     {
-      n = 8 * n + *p - '0';
+      n = 8 * n + p[pos] - '0';
     }
-  p--;
-  *in = p;
+  --pos;
+  *consumed = pos;
   return n;
 }
 
@@ -310,15 +310,14 @@ get_format_specifer_length(char ch)
 bool
 insert_fprintf (struct format_val *vec,
                const struct parser_table *entry,
-               const char *format_const)
+               char *format)
 {
-  char *segstart = (char*)format_const; /* XXX: casting away constness */
-  char *fmt_editpos; /* Current address in scanning `format_const'. */
-  const char *fmt_inpos; /* Address inside of element being scanned. */
+  char *segstart = format;
+  char *fmt_editpos;      /* Current address in scanning `format'. */
   struct segment **segmentp;     /* Address of current segment. */
   struct predicate *our_pred;
 
-  our_pred = insert_primary_withpred (entry, pred_fprintf, format_const);
+  our_pred = insert_primary_withpred (entry, pred_fprintf, format);
   our_pred->side_effects = our_pred->no_default_print = true;
   our_pred->args.printf_vec = *vec;
   our_pred->need_type = false;
@@ -341,14 +340,16 @@ insert_fprintf (struct format_val *vec,
        }
       else if (*fmt_editpos == '\\')
        {
-         fmt_inpos = fmt_editpos + 1;
-         if (is_octal_char(fmt_editpos[1]))
+         size_t readpos = 1;
+         if (is_octal_char(fmt_editpos[readpos]))
            {
-             *fmt_editpos = parse_octal_escape(&fmt_inpos);
+             size_t consumed = 0;
+             *fmt_editpos = parse_octal_escape(fmt_editpos + readpos, 
&consumed);
+             readpos += consumed;
            }
          else
            {
-             const char val = parse_escape_char(fmt_editpos[1]);
+             const char val = parse_escape_char(fmt_editpos[readpos]);
              if (val)
                {
                  fmt_editpos[0] = val;
@@ -356,8 +357,8 @@ insert_fprintf (struct format_val *vec,
              else
                {
                  error (0, 0, _("warning: unrecognized escape `\\%c'"),
-                        fmt_editpos[1]);
-                 fmt_editpos++;
+                        fmt_editpos[readpos]);
+                 fmt_editpos += readpos;
                  continue;
                }
            }
@@ -365,66 +366,61 @@ insert_fprintf (struct format_val *vec,
                                   segstart, fmt_editpos - segstart + 1,
                                   KIND_PLAIN, 0, 0,
                                   our_pred);
-         segstart = fmt_inpos + 1; /* Move past the escape. */
-         fmt_editpos = fmt_inpos;  /* Incremented immediately by `for'. */
+         segstart = fmt_editpos + readpos + 1; /* Move past the escape. */
+         fmt_editpos += readpos;  /* Incremented immediately by `for'. */
        }
       else if (fmt_editpos[0] == '%')
        {
          size_t len;
-         fmt_inpos = fmt_editpos;
-         if (fmt_inpos[1] == 0)
+         if (fmt_editpos[1] == 0)
            {
              /* Trailing %.  We don't like those. */
              error (EXIT_FAILURE, 0,
-                    _("error: %s at end of format string"), fmt_inpos);
+                    _("error: %s at end of format string"), fmt_editpos);
            }
 
-         if (fmt_inpos[1] == '%') /* %% produces just %. */
+         if (fmt_editpos[1] == '%') /* %% produces just %. */
            len = 1;
          else
-           len = get_format_flags_length(fmt_inpos);
-         fmt_inpos += len;
+           len = get_format_flags_length(fmt_editpos);
          fmt_editpos += len;
 
-         assert (fmt_inpos == fmt_editpos);
-         len = get_format_specifer_length (fmt_inpos[0]);
-         if (len && (fmt_inpos[len-1]))
+         len = get_format_specifer_length (fmt_editpos[0]);
+         if (len && (fmt_editpos[len-1]))
            {
-             const char fmt2 = (len == 2) ? fmt_inpos[1] : 0;
+             const char fmt2 = (len == 2) ? fmt_editpos[1] : 0;
              segmentp = make_segment (segmentp, segstart,
                                       fmt_editpos - segstart,
-                                      KIND_FORMAT, *fmt_inpos, fmt2,
+                                      KIND_FORMAT, fmt_editpos[0], fmt2,
                                       our_pred);
              fmt_editpos += (len - 1);
-             fmt_inpos += (len - 1);
            }
          else
            {
-             if (strchr ("{[(", *fmt_inpos))
+             if (strchr ("{[(", fmt_editpos[0]))
                {
                  error (EXIT_FAILURE, 0,
                         _("error: the format directive `%%%c' is reserved for 
future use"),
-                        (int)*fmt_inpos);
+                        (int)fmt_editpos[0]);
                  /*NOTREACHED*/
                }
 
-             if (len == 2 && !fmt_inpos[1])
+             if (len == 2 && !fmt_editpos[1])
                {
                  error (0, 0,
                         _("warning: format directive `%%%c' "
                           "should be followed by another character"),
-                        *fmt_inpos);
+                        fmt_editpos[0]);
                }
              else
                {
                  /* An unrecognized % escape.  Print the char after the %. */
                  error (0, 0,
                         _("warning: unrecognized format directive `%%%c'"),
-                        *fmt_inpos);
+                        fmt_editpos[0]);
                }
-             ++fmt_inpos;
              segmentp = make_segment (segmentp,
-                                      segstart, fmt_inpos - segstart,
+                                      segstart, fmt_editpos + 1 - segstart,
                                       KIND_PLAIN, 0, 0,
                                       our_pred);
            }
diff --git a/find/print.h b/find/print.h
index 4ae0307..33883c6 100644
--- a/find/print.h
+++ b/find/print.h
@@ -13,4 +13,4 @@ struct segment **make_segment (struct segment **segment,
 bool
 insert_fprintf (struct format_val *vec,
                const struct parser_table *entry,
-               const char *format_const);
+               char *format);
-- 
1.7.2.5