gdbsupport: Adapt construct_inferior_arguments

Allow construct_inferior_arguments to handle zero args
and have it return a std::string, similar to how
stringify_argv in gdbsupport/common-utils does.

Also, add a const qualifier for the second parameter,
since it is only read, not written to.

The intention is to replace existing uses of
stringify_argv by construct_inferior_arguments
in a subsequent step, since construct_inferior_arguments
properly handles special characters, while stringify_argv
doesn't.

gdbsupport/ChangeLog:

	* common-inferior.cc, common-inferior.h (construct_inferior_arguments):
	Adapt to handle zero args and return a std::string.
	Adapt call site.

Change-Id: I126c4390a1018c7527b0b8fd545252ab8a5a7adc

diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index cf6e540e79587a41a98d1748e9dcad58e9c73884..ffcc364f64942a626660f04c5c5c8505a1a8926e 100644 (file)
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -151,12 +151,9 @@ get_inferior_args (void)
 {
   if (current_inferior ()->argc != 0)
     {
-      char *n;
-
-      n = construct_inferior_arguments (current_inferior ()->argc,
-                                       current_inferior ()->argv);
-      set_inferior_args (n);
-      xfree (n);
+      std::string n = construct_inferior_arguments (current_inferior ()->argc,
+                                                   current_inferior ()->argv);
+      set_inferior_args (n.c_str ());
     }
 
   if (current_inferior ()->args == NULL)

diff --git a/gdbsupport/ChangeLog b/gdbsupport/ChangeLog
index 4f72c7dd15c201d30806f0f0d58b147e858ff419..67dcdeec07d48e7b9b60d49844d9dfd8f7103151 100644 (file)
--- a/gdbsupport/ChangeLog
+++ b/gdbsupport/ChangeLog
@@ -1,3 +1,9 @@
+2020-05-25  Michael Weghorn  <m.weghorn@posteo.de>
+
+       * common-inferior.cc, common-inferior.h (construct_inferior_arguments):
+       Adapt to handle zero args and return a std::string.
+       Adapt call site.
+
 2020-05-25  Michael Weghorn  <m.weghorn@posteo.de>
 
        * common-inferior.h, common-inferior.cc: (construct_inferior_arguments):

diff --git a/gdbsupport/common-inferior.cc b/gdbsupport/common-inferior.cc
index a7d631f3574d64aacd171eaf594a94b1625ceb45..aa8be14c742677f2ace41dea5f87cf2522d30c22 100644 (file)
--- a/gdbsupport/common-inferior.cc
+++ b/gdbsupport/common-inferior.cc
@@ -27,15 +27,12 @@ bool startup_with_shell = true;
 
 /* See common-inferior.h.  */
 
-char *
-construct_inferior_arguments (int argc, char **argv)
+std::string
+construct_inferior_arguments (int argc, char * const *argv)
 {
-  char *result;
+  gdb_assert (argc >= 0);
 
-  /* ARGC should always be at least 1, but we double check this
-     here.  This is also needed to silence -Werror-stringop
-     warnings.  */
-  gdb_assert (argc > 0);
+  std::string result;
 
   if (startup_with_shell)
     {
@@ -51,49 +48,38 @@ construct_inferior_arguments (int argc, char **argv)
       static const char special[] = "\"!#$&*()\\|[]{}<>?'`~^; \t\n";
       static const char quote = '\'';
 #endif
-      int i;
-      int length = 0;
-      char *out, *cp;
-
-      /* We over-compute the size.  It shouldn't matter.  */
-      for (i = 0; i < argc; ++i)
-       length += 3 * strlen (argv[i]) + 1 + 2 * (argv[i][0] == '\0');
-
-      result = (char *) xmalloc (length);
-      out = result;
-
-      for (i = 0; i < argc; ++i)
+      for (int i = 0; i < argc; ++i)
        {
          if (i > 0)
-           *out++ = ' ';
+           result += ' ';
 
          /* Need to handle empty arguments specially.  */
          if (argv[i][0] == '\0')
            {
-             *out++ = quote;
-             *out++ = quote;
+             result += quote;
+             result += quote;
            }
          else
            {
 #ifdef __MINGW32__
-             int quoted = 0;
+             bool quoted = false;
 
              if (strpbrk (argv[i], special))
                {
-                 quoted = 1;
-                 *out++ = quote;
+                 quoted = true;
+                 result += quote;
                }
 #endif
-             for (cp = argv[i]; *cp; ++cp)
+             for (char *cp = argv[i]; *cp; ++cp)
                {
                  if (*cp == '\n')
                    {
                      /* A newline cannot be quoted with a backslash (it
                         just disappears), only by putting it inside
                         quotes.  */
-                     *out++ = quote;
-                     *out++ = '\n';
-                     *out++ = quote;
+                     result += quote;
+                     result += '\n';
+                     result += quote;
                    }
                  else
                    {
@@ -102,26 +88,22 @@ construct_inferior_arguments (int argc, char **argv)
 #else
                      if (strchr (special, *cp) != NULL)
 #endif
-                       *out++ = '\\';
-                     *out++ = *cp;
+                       result += '\\';
+                     result += *cp;
                    }
                }
 #ifdef __MINGW32__
              if (quoted)
-               *out++ = quote;
+               result += quote;
 #endif
            }
        }
-      *out = '\0';
     }
   else
     {
       /* In this case we can't handle arguments that contain spaces,
         tabs, or newlines -- see breakup_args().  */
-      int i;
-      int length = 0;
-
-      for (i = 0; i < argc; ++i)
+      for (int i = 0; i < argc; ++i)
        {
          char *cp = strchr (argv[i], ' ');
          if (cp == NULL)
@@ -131,16 +113,13 @@ construct_inferior_arguments (int argc, char **argv)
          if (cp != NULL)
            error (_("can't handle command-line "
                     "argument containing whitespace"));
-         length += strlen (argv[i]) + 1;
        }
 
-      result = (char *) xmalloc (length);
-      result[0] = '\0';
-      for (i = 0; i < argc; ++i)
+      for (int i = 0; i < argc; ++i)
        {
          if (i > 0)
-           strcat (result, " ");
-         strcat (result, argv[i]);
+           result += " ";
+         result += argv[i];
        }
     }
 

diff --git a/gdbsupport/common-inferior.h b/gdbsupport/common-inferior.h
index ee87bc75a3f33032d033f515f819520e841ffa15..5e9fc8b0b913920bf6e35e8992e38ca12f086d25 100644 (file)
--- a/gdbsupport/common-inferior.h
+++ b/gdbsupport/common-inferior.h
@@ -60,6 +60,6 @@ extern bool startup_with_shell;
 
 /* Compute command-line string given argument vector. This does the
    same shell processing as fork_inferior.  */
-extern char *construct_inferior_arguments (int, char **);
+extern std::string construct_inferior_arguments (int, char * const *);
 
 #endif /* COMMON_COMMON_INFERIOR_H */