[3/7] elf: Split dl-printf.c from dl-misc.c

Message ID 905c03a4ee231961ca1dd4fc74e49ebf97299b0d.1642162312.git.fweimer@redhat.com
State New
Headers show
Series
  • Reliable CPU compatibility diagnostics in ld.so
Related show

Commit Message

Sunil K Pandey via Libc-alpha Jan. 14, 2022, 12:40 p.m.
This allows to use different compiler flags for the diagnostics
code.
---
 elf/Makefile    |   2 +-
 elf/dl-misc.c   | 281 +---------------------------------------------
 elf/dl-printf.c | 292 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 297 insertions(+), 278 deletions(-)
 create mode 100644 elf/dl-printf.c

-- 
2.34.1

Comments

Sunil K Pandey via Libc-alpha Jan. 14, 2022, 2:25 p.m. | #1
On Fri, Jan 14, 2022 at 4:42 AM Florian Weimer via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>

> This allows to use different compiler flags for the diagnostics

> code.

> ---

>  elf/Makefile    |   2 +-

>  elf/dl-misc.c   | 281 +---------------------------------------------

>  elf/dl-printf.c | 292 ++++++++++++++++++++++++++++++++++++++++++++++++

>  3 files changed, 297 insertions(+), 278 deletions(-)

>  create mode 100644 elf/dl-printf.c

>

> diff --git a/elf/Makefile b/elf/Makefile

> index b86d116be9..0c4be43deb 100644

> --- a/elf/Makefile

> +++ b/elf/Makefile

> @@ -31,7 +31,7 @@ routines      = $(all-dl-routines) dl-support dl-iteratephdr \

>  # The core dynamic linking functions are in libc for the static and

>  # profiled libraries.

>  dl-routines    = $(addprefix dl-,load lookup object reloc deps \

> -                                 runtime init fini debug misc \

> +                                 runtime init fini debug misc printf \

>                                   version profile tls origin scope \

>                                   execstack open close trampoline \

>                                   exception sort-maps lookup-direct \


Should we put one item per-line now?


-- 
H.J.
Sunil K Pandey via Libc-alpha Jan. 14, 2022, 2:27 p.m. | #2
* H. J. Lu:

> On Fri, Jan 14, 2022 at 4:42 AM Florian Weimer via Libc-alpha

> <libc-alpha@sourceware.org> wrote:

>>

>> This allows to use different compiler flags for the diagnostics

>> code.

>> ---

>>  elf/Makefile    |   2 +-

>>  elf/dl-misc.c   | 281 +---------------------------------------------

>>  elf/dl-printf.c | 292 ++++++++++++++++++++++++++++++++++++++++++++++++

>>  3 files changed, 297 insertions(+), 278 deletions(-)

>>  create mode 100644 elf/dl-printf.c

>>

>> diff --git a/elf/Makefile b/elf/Makefile

>> index b86d116be9..0c4be43deb 100644

>> --- a/elf/Makefile

>> +++ b/elf/Makefile

>> @@ -31,7 +31,7 @@ routines      = $(all-dl-routines) dl-support dl-iteratephdr \

>>  # The core dynamic linking functions are in libc for the static and

>>  # profiled libraries.

>>  dl-routines    = $(addprefix dl-,load lookup object reloc deps \

>> -                                 runtime init fini debug misc \

>> +                                 runtime init fini debug misc printf \

>>                                   version profile tls origin scope \

>>                                   execstack open close trampoline \

>>                                   exception sort-maps lookup-direct \

>

> Should we put one item per-line now?


And drop the addprefix?  I can submit a separate patch for that.

Thanks,
Florian
Sunil K Pandey via Libc-alpha Jan. 14, 2022, 2:32 p.m. | #3
On Fri, Jan 14, 2022 at 6:27 AM Florian Weimer <fweimer@redhat.com> wrote:
>

> * H. J. Lu:

>

> > On Fri, Jan 14, 2022 at 4:42 AM Florian Weimer via Libc-alpha

> > <libc-alpha@sourceware.org> wrote:

> >>

> >> This allows to use different compiler flags for the diagnostics

> >> code.

> >> ---

> >>  elf/Makefile    |   2 +-

> >>  elf/dl-misc.c   | 281 +---------------------------------------------

> >>  elf/dl-printf.c | 292 ++++++++++++++++++++++++++++++++++++++++++++++++

> >>  3 files changed, 297 insertions(+), 278 deletions(-)

> >>  create mode 100644 elf/dl-printf.c

> >>

> >> diff --git a/elf/Makefile b/elf/Makefile

> >> index b86d116be9..0c4be43deb 100644

> >> --- a/elf/Makefile

> >> +++ b/elf/Makefile

> >> @@ -31,7 +31,7 @@ routines      = $(all-dl-routines) dl-support dl-iteratephdr \

> >>  # The core dynamic linking functions are in libc for the static and

> >>  # profiled libraries.

> >>  dl-routines    = $(addprefix dl-,load lookup object reloc deps \

> >> -                                 runtime init fini debug misc \

> >> +                                 runtime init fini debug misc printf \

> >>                                   version profile tls origin scope \

> >>                                   execstack open close trampoline \

> >>                                   exception sort-maps lookup-direct \

> >

> > Should we put one item per-line now?

>

> And drop the addprefix?  I can submit a separate patch for that.


Yes.  It will make adding the next file a bit easier.

> Thanks,

> Florian

>



-- 
H.J.

Patch

diff --git a/elf/Makefile b/elf/Makefile
index b86d116be9..0c4be43deb 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -31,7 +31,7 @@  routines	= $(all-dl-routines) dl-support dl-iteratephdr \
 # The core dynamic linking functions are in libc for the static and
 # profiled libraries.
 dl-routines	= $(addprefix dl-,load lookup object reloc deps \
-				  runtime init fini debug misc \
+				  runtime init fini debug misc printf \
 				  version profile tls origin scope \
 				  execstack open close trampoline \
 				  exception sort-maps lookup-direct \
diff --git a/elf/dl-misc.c b/elf/dl-misc.c
index 452b79de4a..6f40c28820 100644
--- a/elf/dl-misc.c
+++ b/elf/dl-misc.c
@@ -16,24 +16,16 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <assert.h>
+#include <_itoa.h>
 #include <fcntl.h>
 #include <ldsodefs.h>
-#include <limits.h>
 #include <link.h>
-#include <stdarg.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
+#include <not-cancel.h>
 #include <stdint.h>
+#include <stdlib.h>
 #include <sys/mman.h>
-#include <sys/param.h>
 #include <sys/stat.h>
-#include <sys/uio.h>
-#include <sysdep.h>
-#include <_itoa.h>
-#include <dl-writev.h>
-#include <not-cancel.h>
+#include <unistd.h>
 
 /* Read the whole contents of FILE into new mmap'd space with given
    protections.  *SIZEP gets the size of the file.  On error MAP_FAILED
@@ -70,270 +62,6 @@  _dl_sysdep_read_whole_file (const char *file, size_t *sizep, int prot)
   return result;
 }
 
-
-/* Bare-bones printf implementation.  This function only knows about
-   the formats and flags needed and can handle only up to 64 stripes in
-   the output.  */
-static void
-_dl_debug_vdprintf (int fd, int tag_p, const char *fmt, va_list arg)
-{
-# define NIOVMAX 64
-  struct iovec iov[NIOVMAX];
-  int niov = 0;
-  pid_t pid = 0;
-  char pidbuf[12];
-
-  while (*fmt != '\0')
-    {
-      const char *startp = fmt;
-
-      if (tag_p > 0)
-	{
-	  /* Generate the tag line once.  It consists of the PID and a
-	     colon followed by a tab.  */
-	  if (pid == 0)
-	    {
-	      char *p;
-	      pid = __getpid ();
-	      assert (pid >= 0 && sizeof (pid_t) <= 4);
-	      p = _itoa (pid, &pidbuf[10], 10, 0);
-	      while (p > pidbuf)
-		*--p = ' ';
-	      pidbuf[10] = ':';
-	      pidbuf[11] = '\t';
-	    }
-
-	  /* Append to the output.  */
-	  assert (niov < NIOVMAX);
-	  iov[niov].iov_len = 12;
-	  iov[niov++].iov_base = pidbuf;
-
-	  /* No more tags until we see the next newline.  */
-	  tag_p = -1;
-	}
-
-      /* Skip everything except % and \n (if tags are needed).  */
-      while (*fmt != '\0' && *fmt != '%' && (! tag_p || *fmt != '\n'))
-	++fmt;
-
-      /* Append constant string.  */
-      assert (niov < NIOVMAX);
-      if ((iov[niov].iov_len = fmt - startp) != 0)
-	iov[niov++].iov_base = (char *) startp;
-
-      if (*fmt == '%')
-	{
-	  /* It is a format specifier.  */
-	  char fill = ' ';
-	  int width = -1;
-	  int prec = -1;
-#if LONG_MAX != INT_MAX
-	  int long_mod = 0;
-#endif
-
-	  /* Recognize zero-digit fill flag.  */
-	  if (*++fmt == '0')
-	    {
-	      fill = '0';
-	      ++fmt;
-	    }
-
-	  /* See whether with comes from a parameter.  Note that no other
-	     way to specify the width is implemented.  */
-	  if (*fmt == '*')
-	    {
-	      width = va_arg (arg, int);
-	      ++fmt;
-	    }
-
-	  /* Handle precision.  */
-	  if (*fmt == '.' && fmt[1] == '*')
-	    {
-	      prec = va_arg (arg, int);
-	      fmt += 2;
-	    }
-
-	  /* Recognize the l modifier.  It is only important on some
-	     platforms where long and int have a different size.  We
-	     can use the same code for size_t.  */
-	  if (*fmt == 'l' || *fmt == 'Z')
-	    {
-#if LONG_MAX != INT_MAX
-	      long_mod = 1;
-#endif
-	      ++fmt;
-	    }
-
-	  switch (*fmt)
-	    {
-	      /* Integer formatting.  */
-	    case 'd':
-	    case 'u':
-	    case 'x':
-	      {
-		/* We have to make a difference if long and int have a
-		   different size.  */
-#if LONG_MAX != INT_MAX
-		unsigned long int num = (long_mod
-					 ? va_arg (arg, unsigned long int)
-					 : va_arg (arg, unsigned int));
-#else
-		unsigned long int num = va_arg (arg, unsigned int);
-#endif
-		bool negative = false;
-		if (*fmt == 'd')
-		  {
-#if LONG_MAX != INT_MAX
-		    if (long_mod)
-		      {
-			if ((long int) num < 0)
-			  negative = true;
-		      }
-		    else
-		      {
-			if ((int) num < 0)
-			  {
-			    num = (unsigned int) num;
-			    negative = true;
-			  }
-		      }
-#else
-		    if ((int) num < 0)
-		      negative = true;
-#endif
-		  }
-
-		/* We use alloca() to allocate the buffer with the most
-		   pessimistic guess for the size.  Using alloca() allows
-		   having more than one integer formatting in a call.  */
-		char *buf = (char *) alloca (1 + 3 * sizeof (unsigned long int));
-		char *endp = &buf[1 + 3 * sizeof (unsigned long int)];
-		char *cp = _itoa (num, endp, *fmt == 'x' ? 16 : 10, 0);
-
-		/* Pad to the width the user specified.  */
-		if (width != -1)
-		  while (endp - cp < width)
-		    *--cp = fill;
-
-		if (negative)
-		  *--cp = '-';
-
-		iov[niov].iov_base = cp;
-		iov[niov].iov_len = endp - cp;
-		++niov;
-	      }
-	      break;
-
-	    case 's':
-	      /* Get the string argument.  */
-	      iov[niov].iov_base = va_arg (arg, char *);
-	      iov[niov].iov_len = strlen (iov[niov].iov_base);
-	      if (prec != -1)
-		iov[niov].iov_len = MIN ((size_t) prec, iov[niov].iov_len);
-	      ++niov;
-	      break;
-
-	    case '%':
-	      iov[niov].iov_base = (void *) fmt;
-	      iov[niov].iov_len = 1;
-	      ++niov;
-	      break;
-
-	    default:
-	      assert (! "invalid format specifier");
-	    }
-	  ++fmt;
-	}
-      else if (*fmt == '\n')
-	{
-	  /* See whether we have to print a single newline character.  */
-	  if (fmt == startp)
-	    {
-	      iov[niov].iov_base = (char *) startp;
-	      iov[niov++].iov_len = 1;
-	    }
-	  else
-	    /* No, just add it to the rest of the string.  */
-	    ++iov[niov - 1].iov_len;
-
-	  /* Next line, print a tag again.  */
-	  tag_p = 1;
-	  ++fmt;
-	}
-    }
-
-  /* Finally write the result.  */
-  _dl_writev (fd, iov, niov);
-}
-
-
-/* Write to debug file.  */
-void
-_dl_debug_printf (const char *fmt, ...)
-{
-  va_list arg;
-
-  va_start (arg, fmt);
-  _dl_debug_vdprintf (GLRO(dl_debug_fd), 1, fmt, arg);
-  va_end (arg);
-}
-
-
-/* Write to debug file but don't start with a tag.  */
-void
-_dl_debug_printf_c (const char *fmt, ...)
-{
-  va_list arg;
-
-  va_start (arg, fmt);
-  _dl_debug_vdprintf (GLRO(dl_debug_fd), -1, fmt, arg);
-  va_end (arg);
-}
-
-
-/* Write the given file descriptor.  */
-void
-_dl_dprintf (int fd, const char *fmt, ...)
-{
-  va_list arg;
-
-  va_start (arg, fmt);
-  _dl_debug_vdprintf (fd, 0, fmt, arg);
-  va_end (arg);
-}
-
-void
-_dl_printf (const char *fmt, ...)
-{
-  va_list arg;
-
-  va_start (arg, fmt);
-  _dl_debug_vdprintf (STDOUT_FILENO, 0, fmt, arg);
-  va_end (arg);
-}
-
-void
-_dl_error_printf (const char *fmt, ...)
-{
-  va_list arg;
-
-  va_start (arg, fmt);
-  _dl_debug_vdprintf (STDERR_FILENO, 0, fmt, arg);
-  va_end (arg);
-}
-
-void
-_dl_fatal_printf (const char *fmt, ...)
-{
-  va_list arg;
-
-  va_start (arg, fmt);
-  _dl_debug_vdprintf (STDERR_FILENO, 0, fmt, arg);
-  va_end (arg);
-  _exit (127);
-}
-rtld_hidden_def (_dl_fatal_printf)
-
 /* Test whether given NAME matches any of the names of the given object.  */
 int
 _dl_name_match_p (const char *name, const struct link_map *map)
@@ -354,7 +82,6 @@  _dl_name_match_p (const char *name, const struct link_map *map)
   return 0;
 }
 
-
 unsigned long int
 _dl_higher_prime_number (unsigned long int n)
 {
diff --git a/elf/dl-printf.c b/elf/dl-printf.c
new file mode 100644
index 0000000000..d3264ba96c
--- /dev/null
+++ b/elf/dl-printf.c
@@ -0,0 +1,292 @@ 
+/* printf implementation for the dynamic loader.
+   Copyright (C) 1997-2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <_itoa.h>
+#include <assert.h>
+#include <dl-writev.h>
+#include <ldsodefs.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/uio.h>
+#include <unistd.h>
+
+/* Bare-bones printf implementation.  This function only knows about
+   the formats and flags needed and can handle only up to 64 stripes in
+   the output.  */
+static void
+_dl_debug_vdprintf (int fd, int tag_p, const char *fmt, va_list arg)
+{
+# define NIOVMAX 64
+  struct iovec iov[NIOVMAX];
+  int niov = 0;
+  pid_t pid = 0;
+  char pidbuf[12];
+
+  while (*fmt != '\0')
+    {
+      const char *startp = fmt;
+
+      if (tag_p > 0)
+	{
+	  /* Generate the tag line once.  It consists of the PID and a
+	     colon followed by a tab.  */
+	  if (pid == 0)
+	    {
+	      char *p;
+	      pid = __getpid ();
+	      assert (pid >= 0 && sizeof (pid_t) <= 4);
+	      p = _itoa (pid, &pidbuf[10], 10, 0);
+	      while (p > pidbuf)
+		*--p = ' ';
+	      pidbuf[10] = ':';
+	      pidbuf[11] = '\t';
+	    }
+
+	  /* Append to the output.  */
+	  assert (niov < NIOVMAX);
+	  iov[niov].iov_len = 12;
+	  iov[niov++].iov_base = pidbuf;
+
+	  /* No more tags until we see the next newline.  */
+	  tag_p = -1;
+	}
+
+      /* Skip everything except % and \n (if tags are needed).  */
+      while (*fmt != '\0' && *fmt != '%' && (! tag_p || *fmt != '\n'))
+	++fmt;
+
+      /* Append constant string.  */
+      assert (niov < NIOVMAX);
+      if ((iov[niov].iov_len = fmt - startp) != 0)
+	iov[niov++].iov_base = (char *) startp;
+
+      if (*fmt == '%')
+	{
+	  /* It is a format specifier.  */
+	  char fill = ' ';
+	  int width = -1;
+	  int prec = -1;
+#if LONG_MAX != INT_MAX
+	  int long_mod = 0;
+#endif
+
+	  /* Recognize zero-digit fill flag.  */
+	  if (*++fmt == '0')
+	    {
+	      fill = '0';
+	      ++fmt;
+	    }
+
+	  /* See whether with comes from a parameter.  Note that no other
+	     way to specify the width is implemented.  */
+	  if (*fmt == '*')
+	    {
+	      width = va_arg (arg, int);
+	      ++fmt;
+	    }
+
+	  /* Handle precision.  */
+	  if (*fmt == '.' && fmt[1] == '*')
+	    {
+	      prec = va_arg (arg, int);
+	      fmt += 2;
+	    }
+
+	  /* Recognize the l modifier.  It is only important on some
+	     platforms where long and int have a different size.  We
+	     can use the same code for size_t.  */
+	  if (*fmt == 'l' || *fmt == 'Z')
+	    {
+#if LONG_MAX != INT_MAX
+	      long_mod = 1;
+#endif
+	      ++fmt;
+	    }
+
+	  switch (*fmt)
+	    {
+	      /* Integer formatting.  */
+	    case 'd':
+	    case 'u':
+	    case 'x':
+	      {
+		/* We have to make a difference if long and int have a
+		   different size.  */
+#if LONG_MAX != INT_MAX
+		unsigned long int num = (long_mod
+					 ? va_arg (arg, unsigned long int)
+					 : va_arg (arg, unsigned int));
+#else
+		unsigned long int num = va_arg (arg, unsigned int);
+#endif
+		bool negative = false;
+		if (*fmt == 'd')
+		  {
+#if LONG_MAX != INT_MAX
+		    if (long_mod)
+		      {
+			if ((long int) num < 0)
+			  negative = true;
+		      }
+		    else
+		      {
+			if ((int) num < 0)
+			  {
+			    num = (unsigned int) num;
+			    negative = true;
+			  }
+		      }
+#else
+		    if ((int) num < 0)
+		      negative = true;
+#endif
+		  }
+
+		/* We use alloca() to allocate the buffer with the most
+		   pessimistic guess for the size.  Using alloca() allows
+		   having more than one integer formatting in a call.  */
+		char *buf = (char *) alloca (1 + 3 * sizeof (unsigned long int));
+		char *endp = &buf[1 + 3 * sizeof (unsigned long int)];
+		char *cp = _itoa (num, endp, *fmt == 'x' ? 16 : 10, 0);
+
+		/* Pad to the width the user specified.  */
+		if (width != -1)
+		  while (endp - cp < width)
+		    *--cp = fill;
+
+		if (negative)
+		  *--cp = '-';
+
+		iov[niov].iov_base = cp;
+		iov[niov].iov_len = endp - cp;
+		++niov;
+	      }
+	      break;
+
+	    case 's':
+	      /* Get the string argument.  */
+	      iov[niov].iov_base = va_arg (arg, char *);
+	      iov[niov].iov_len = strlen (iov[niov].iov_base);
+	      if (prec != -1)
+		iov[niov].iov_len = MIN ((size_t) prec, iov[niov].iov_len);
+	      ++niov;
+	      break;
+
+	    case '%':
+	      iov[niov].iov_base = (void *) fmt;
+	      iov[niov].iov_len = 1;
+	      ++niov;
+	      break;
+
+	    default:
+	      assert (! "invalid format specifier");
+	    }
+	  ++fmt;
+	}
+      else if (*fmt == '\n')
+	{
+	  /* See whether we have to print a single newline character.  */
+	  if (fmt == startp)
+	    {
+	      iov[niov].iov_base = (char *) startp;
+	      iov[niov++].iov_len = 1;
+	    }
+	  else
+	    /* No, just add it to the rest of the string.  */
+	    ++iov[niov - 1].iov_len;
+
+	  /* Next line, print a tag again.  */
+	  tag_p = 1;
+	  ++fmt;
+	}
+    }
+
+  /* Finally write the result.  */
+  _dl_writev (fd, iov, niov);
+}
+
+
+/* Write to debug file.  */
+void
+_dl_debug_printf (const char *fmt, ...)
+{
+  va_list arg;
+
+  va_start (arg, fmt);
+  _dl_debug_vdprintf (GLRO(dl_debug_fd), 1, fmt, arg);
+  va_end (arg);
+}
+
+
+/* Write to debug file but don't start with a tag.  */
+void
+_dl_debug_printf_c (const char *fmt, ...)
+{
+  va_list arg;
+
+  va_start (arg, fmt);
+  _dl_debug_vdprintf (GLRO(dl_debug_fd), -1, fmt, arg);
+  va_end (arg);
+}
+
+
+/* Write the given file descriptor.  */
+void
+_dl_dprintf (int fd, const char *fmt, ...)
+{
+  va_list arg;
+
+  va_start (arg, fmt);
+  _dl_debug_vdprintf (fd, 0, fmt, arg);
+  va_end (arg);
+}
+
+void
+_dl_printf (const char *fmt, ...)
+{
+  va_list arg;
+
+  va_start (arg, fmt);
+  _dl_debug_vdprintf (STDOUT_FILENO, 0, fmt, arg);
+  va_end (arg);
+}
+
+void
+_dl_error_printf (const char *fmt, ...)
+{
+  va_list arg;
+
+  va_start (arg, fmt);
+  _dl_debug_vdprintf (STDERR_FILENO, 0, fmt, arg);
+  va_end (arg);
+}
+
+void
+_dl_fatal_printf (const char *fmt, ...)
+{
+  va_list arg;
+
+  va_start (arg, fmt);
+  _dl_debug_vdprintf (STDERR_FILENO, 0, fmt, arg);
+  va_end (arg);
+  _exit (127);
+}
+rtld_hidden_def (_dl_fatal_printf)