/usr/src/gnu/usr.bin/texinfo/makeinfo/files.c

Bug Summary

File:	src/gnu/usr.bin/texinfo/makeinfo/files.c
Warning:	line 178, column 27 Null pointer passed as 1st argument to string length function

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name files.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 1 -pic-is-pie -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -target-feature +retpoline-indirect-calls -target-feature +retpoline-indirect-branches -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/gnu/usr.bin/texinfo/obj/makeinfo -resource-dir /usr/local/lib/clang/13.0.0 -D HAVE_CONFIG_H -I . -I /usr/src/gnu/usr.bin/texinfo/makeinfo -I .. -I /usr/src/gnu/usr.bin/texinfo/lib -I ../intl -D LOCALEDIR="/usr/share/locale" -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -fdebug-compilation-dir=/usr/src/gnu/usr.bin/texinfo/obj/makeinfo -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c /usr/src/gnu/usr.bin/texinfo/makeinfo/files.c

1/* files.c -- file-related functions for makeinfo.
 $Id: files.c,v 1.1.1.3 2006/07/17 16:03:46 espie Exp $

 Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software
 Foundation, Inc.

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2, or (at your option)
 any later version.

 This program 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 General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software Foundation,
 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

21#include "system.h"
22#include "files.h"
23#include "html.h"
24#include "index.h"
25#include "macro.h"
26#include "makeinfo.h"
27#include "node.h"

29FSTACK *filestack = NULL((void *)0);

31static int node_filename_stack_index = 0;
32static int node_filename_stack_size = 0;
33static char **node_filename_stack = NULL((void *)0);
34
35/* Looking for include files.  */

37/* Given a string containing units of information separated by colons,
 return the next one pointed to by INDEX, or NULL if there are no more.
 Advance INDEX to the character after the colon. */
40static char *
41extract_colon_unit (char *string, int *index)
42{
int start;
int path_sep_char = PATH_SEP":"[0];
int i = *index;

if (!string || (i >= strlen (string)))
  return NULL((void *)0);

/* Each call to this routine leaves the index pointing at a colon if
   there is more to the path.  If i > 0, then increment past the
   `:'.  If i == 0, then the path has a leading colon.  Trailing colons
   are handled OK by the `else' part of the if statement; an empty
   string is returned in that case. */
if (i && string[i] == path_sep_char)
  i++;

start = i;
while (string[i] && string[i] != path_sep_char) i++;
*index = i;

if (i == start)
  {
    if (string[i])
      (*index)++;

    /* Return "" in the case of a trailing `:'. */
    return xstrdup ("");
  }
else
  {
    char *value;

    value = xmalloc (1 + (i - start));
    memcpy (value, &string[start], (i - start));
    value [i - start] = 0;

    return value;
  }
80}

82/* Return the full pathname for FILENAME by searching along PATH.
 When found, return the stat () info for FILENAME in FINFO.
 If PATH is NULL, only the current directory is searched.
 If the file could not be found, return a NULL pointer. */
86char *
87get_file_info_in_path (char *filename, char *path, struct stat *finfo)
88{
char *dir;
int result, index = 0;

if (path == NULL((void *)0))
  path = ".";

/* Handle absolute pathnames.  */
if (IS_ABSOLUTE (filename)((filename)[0] == '/')
    || (*filename == '.'
        && (IS_SLASH (filename[1])((filename[1]) == '/')
            || (filename[1] == '.' && IS_SLASH (filename[2])((filename[2]) == '/')))))
  {
    if (stat (filename, finfo) == 0)
      return xstrdup (filename);
    else
      return NULL((void *)0);
  }

while ((dir = extract_colon_unit (path, &index)))
  {
    char *fullpath;

    if (!*dir)
      {
        free (dir);
        dir = xstrdup (".");
      }

    fullpath = xmalloc (2 + strlen (dir) + strlen (filename));
    sprintf (fullpath, "%s/%s", dir, filename);
    free (dir);

    result = stat (fullpath, finfo);

    if (result == 0)
      return fullpath;
    else
      free (fullpath);
  }
return NULL((void *)0);
129}

131/* Prepend and append new paths to include_files_path.  */
132void
133prepend_to_include_path (char *path)
134{
if (!include_files_path)
  {
    include_files_path = xstrdup (path);
    include_files_path = xrealloc (include_files_path,
        strlen (include_files_path) + 3); /* 3 for ":.\0" */
    strcat (strcat (include_files_path, PATH_SEP":"), ".");
  }
else
  {
    char *tmp = xstrdup (include_files_path);
    include_files_path = xrealloc (include_files_path,
        strlen (include_files_path) + strlen (path) + 2); /* 2 for ":\0" */
    strcpy (include_files_path, path);
    strcat (include_files_path, PATH_SEP":");
    strcat (include_files_path, tmp);
    free (tmp);
  }
152}

154void
155append_to_include_path (char *path)
156{
if (!include_files_path)
  include_files_path = xstrdup (".");

include_files_path = (char *) xrealloc (include_files_path,
      2 + strlen (include_files_path) + strlen (path));
strcat (include_files_path, PATH_SEP":");
strcat (include_files_path, path);
164}

166/* Remove the first path from the include_files_path.  */
167void
168pop_path_from_include_path (void)
169{
int i = 0;
char *tmp;

if (include_files_path)
1
Assuming 'include_files_path' is null→
2
←
Taking false branch→
  for (i = 0; i < strlen (include_files_path)
      && include_files_path[i] != ':'; i++);

/* Advance include_files_path to the next char from ':'  */
tmp = (char *) xmalloc (strlen (include_files_path) - i);
3
←
Null pointer passed as 1st argument to string length function
strcpy (tmp, (char *) include_files_path + i + 1);

free (include_files_path);
include_files_path = tmp;
183}
184
185/* Find and load the file named FILENAME.  Return a pointer to
 the loaded file, or NULL if it can't be loaded.  If USE_PATH is zero,
 just look for the given file (this is used in handle_delayed_writes),
 else search along include_files_path.   */

190char *
191find_and_load (char *filename, int use_path)
192{
struct stat fileinfo;
long file_size;
int file = -1, count = 0;
char *fullpath, *result;
int n, bytes_to_read;

result = fullpath = NULL((void *)0);

fullpath
  = get_file_info_in_path (filename, use_path ? include_files_path : NULL((void *)0), 
                           &fileinfo);

if (!fullpath)
  goto error_exit;

filename = fullpath;
file_size = (long) fileinfo.st_size;

file = open (filename, O_RDONLY0x0000);
if (file < 0)
  goto error_exit;

/* Load the file, with enough room for a newline and a null. */
result = xmalloc (file_size + 2);

/* VMS stat lies about the st_size value.  The actual number of
   readable bytes is always less than this value.  The arcane
   mysteries of VMS/RMS are too much to probe, so this hack
  suffices to make things work.  It's also needed on Cygwin.  And so
  we might as well use it everywhere.  */
bytes_to_read = file_size;
while ((n = read (file, result + count, bytes_to_read)) > 0)
  {
    count += n;
    bytes_to_read -= n;
  }
if (0 < count && count < file_size)
  result = xrealloc (result, count + 2); /* why waste the slack? */
else if (n == -1)
232error_exit:
  {
    if (result)
      free (result);

    if (fullpath)
      free (fullpath);

    if (file != -1)
      close (file);

    return NULL((void *)0);
  }
close (file);

/* Set the globals to the new file. */
input_text = result;
input_text_length = count;
input_filename = fullpath;
node_filename = xstrdup (fullpath);
input_text_offset = 0;
line_number = 1;
/* Not strictly necessary.  This magic prevents read_token () from doing
   extra unnecessary work each time it is called (that is a lot of times).
   INPUT_TEXT_LENGTH is one past the actual end of the text. */
input_text[input_text_length] = '\n';
/* This, on the other hand, is always necessary.  */
input_text[input_text_length+1] = 0;
return result;
261}
262
263/* Pushing and popping files.  */
264static void
265push_node_filename (void)
266{
if (node_filename_stack_index + 1 > node_filename_stack_size)
  node_filename_stack = xrealloc
  (node_filename_stack, (node_filename_stack_size += 10) * sizeof (char *));

node_filename_stack[node_filename_stack_index] = node_filename;
node_filename_stack_index++;
273}

275static void
276pop_node_filename (void)
277{
node_filename = node_filename_stack[--node_filename_stack_index];
279}

281/* Save the state of the current input file. */
282void
283pushfile (void)
284{
FSTACK *newstack = xmalloc (sizeof (FSTACK));
newstack->filename = input_filename;
newstack->text = input_text;
newstack->size = input_text_length;
newstack->offset = input_text_offset;
newstack->line_number = line_number;
newstack->next = filestack;

filestack = newstack;
push_node_filename ();
295}

297/* Make the current file globals be what is on top of the file stack. */
298void
299popfile (void)
300{
FSTACK *tos = filestack;

if (!tos)
  abort ();                   /* My fault.  I wonder what I did? */

if (macro_expansion_output_stream)
  {
    maybe_write_itext (input_text, input_text_offset);
    forget_itext (input_text);
  }

/* Pop the stack. */
filestack = filestack->next;

/* Make sure that commands with braces have been satisfied. */
if (!executing_string && !me_executing_string)
  discard_braces ();

/* Get the top of the stack into the globals. */
input_filename = tos->filename;
input_text = tos->text;
input_text_length = tos->size;
input_text_offset = tos->offset;
line_number = tos->line_number;
free (tos);

/* Go back to the (now) current node. */
pop_node_filename ();
329}

331/* Flush all open files on the file stack. */
332void
333flush_file_stack (void)
334{
while (filestack)
  {
    char *fname = input_filename;
    char *text = input_text;
    popfile ();
    free (fname);
    free (text);
  }
343}

345/* Return the index of the first character in the filename
 which is past all the leading directory characters.  */
347static int
348skip_directory_part (char *filename)
349{
int i = strlen (filename) - 1;

while (i && !IS_SLASH (filename[i])((filename[i]) == '/'))
  i--;
if (IS_SLASH (filename[i])((filename[i]) == '/'))
  i++;
else if (filename[i] && HAVE_DRIVE (filename)(0))
  i = 2;

return i;
360}

362static char *
363filename_non_directory (char *name)
364{
return xstrdup (name + skip_directory_part (name));
366}

368/* Return just the simple part of the filename; i.e. the
 filename without the path information, or extensions.
 This conses up a new string. */
371char *
372filename_part (char *filename)
373{
char *basename = filename_non_directory (filename);

376#ifdef REMOVE_OUTPUT_EXTENSIONS
/* See if there is an extension to remove.  If so, remove it. */
{
  char *temp = strrchr (basename, '.');
  if (temp)
    *temp = 0;
}
383#endif /* REMOVE_OUTPUT_EXTENSIONS */
return basename;
385}

387/* Return the pathname part of filename.  This can be NULL. */
388char *
389pathname_part (char *filename)
390{
char *result = NULL((void *)0);
int i;

filename = expand_filename (filename, "");

i = skip_directory_part (filename);
if (i)
  {
    result = xmalloc (1 + i);
    strncpy (result, filename, i);
    result[i] = 0;
  }
free (filename);
return result;
405}

407/* Return the full path to FILENAME. */
408static char *
409full_pathname (char *filename)
410{
int initial_character;
char *result;

/* No filename given? */
if (!filename || !*filename)
  return xstrdup ("");

/* Already absolute? */
if (IS_ABSOLUTE (filename)((filename)[0] == '/') ||
    (*filename == '.' &&
     (IS_SLASH (filename[1])((filename[1]) == '/') ||
      (filename[1] == '.' && IS_SLASH (filename[2])((filename[2]) == '/')))))
  return xstrdup (filename);

initial_character = *filename;
if (initial_character != '~')
  {
    char *localdir = xmalloc (1025);
429#ifdef HAVE_GETCWD1
    if (!getcwd (localdir, 1024))
431#else
    if (!getwd (localdir))
433#endif
      {
        fprintf (stderr(&__sF[2]), _("%s: getwd: %s, %s\n")((const char *) ("%s: getwd: %s, %s\n")),
                 progname, filename, localdir);
        xexit (1);
      }

    strcat (localdir, "/");
    strcat (localdir, filename);
    result = xstrdup (localdir);
    free (localdir);
  }
else
  { /* Does anybody know why WIN32 doesn't want to support $HOME?
       If the reason is they don't have getpwnam, they should
       only disable the else clause below.  */
449#ifndef WIN32
    if (IS_SLASH (filename[1])((filename[1]) == '/'))
      {
        /* Return the concatenation of the environment variable HOME
           and the rest of the string. */
        char *temp_home;

        temp_home = (char *) getenv ("HOME");
        result = xmalloc (strlen (&filename[1])
                                  + 1
                                  + temp_home ? strlen (temp_home)
                                  : 0);
        *result = 0;

        if (temp_home)
          strcpy (result, temp_home);

        strcat (result, &filename[1]);
      }
    else
      {
        struct passwd *user_entry;
        int i, c;
        char *username = xmalloc (257);

        for (i = 1; (c = filename[i]); i++)
          {
            if (IS_SLASH (c)((c) == '/'))
              break;
            else
              username[i - 1] = c;
          }
        if (c)
          username[i - 1] = 0;

        user_entry = getpwnam (username);

        if (!user_entry)
          return xstrdup (filename);

        result = xmalloc (1 + strlen (user_entry->pw_dir)
                                  + strlen (&filename[i]));
        strcpy (result, user_entry->pw_dir);
        strcat (result, &filename[i]);
      }
494#endif /* not WIN32 */
  }
return result;
497}

499/* Return the expansion of FILENAME. */
500char *
501expand_filename (char *filename, char *input_name)
502{
int i;

if (filename)
  {
    filename = full_pathname (filename);
    if (IS_ABSOLUTE (filename)((filename)[0] == '/')
 || (*filename == '.' &&
     (IS_SLASH (filename[1])((filename[1]) == '/') ||
      (filename[1] == '.' && IS_SLASH (filename[2])((filename[2]) == '/')))))
return filename;
  }
else
  {
    filename = filename_non_directory (input_name);

    if (!*filename)
      {
        free (filename);
        filename = xstrdup ("noname.texi");
      }

    for (i = strlen (filename) - 1; i; i--)
      if (filename[i] == '.')
        break;

    if (!i)
      i = strlen (filename);

    if (i + 6 > (strlen (filename)))
      filename = xrealloc (filename, i + 6);
    strcpy (filename + i, html ? ".html" : ".info");
    return filename;
  }

if (IS_ABSOLUTE (input_name)((input_name)[0] == '/'))
  {
    /* Make it so that relative names work. */
    char *result;
    
    i = strlen (input_name) - 1;

    result = xmalloc (1 + strlen (input_name) + strlen (filename));
    strcpy (result, input_name);

    while (!IS_SLASH (result[i])((result[i]) == '/') && i)
      i--;
    if (IS_SLASH (result[i])((result[i]) == '/'))
      i++;

    strcpy (&result[i], filename);
    free (filename);
    return result;
  }
return filename;
557}

559char *
560output_name_from_input_name (char *name)
561{
return expand_filename (NULL((void *)0), name);
563}


566/* Modify the file name FNAME so that it fits the limitations of the
 underlying filesystem.  In particular, truncate the file name as it
 would be truncated by the filesystem.  We assume the result can
 never be longer than the original, otherwise we couldn't be sure we
 have enough space in the original string to modify it in place.  */
571char *
572normalize_filename (char *fname)
573{
int maxlen;
char orig[PATH_MAX1024 + 1];
int i;
char *lastdot, *p;

579#ifdef _PC_NAME_MAX4
maxlen = pathconf (fname, _PC_NAME_MAX4);
if (maxlen < 1)
582#endif
  maxlen = PATH_MAX1024;

i = skip_directory_part (fname);
if (fname[i] == '\0')
  return fname;	/* only a directory name -- don't modify */
strcpy (orig, fname + i);

switch (maxlen)
  {
    case 12:	/* MS-DOS 8+3 filesystem */
if (orig[0] == '.')	/* leading dots are not allowed */
 orig[0] = '_';
lastdot = strrchr (orig, '.');
if (!lastdot)
 lastdot = orig + strlen (orig);
strncpy (fname + i, orig, lastdot - orig);
for (p = fname + i;
    p < fname + i + (lastdot - orig) && p < fname + i + 8;
    p++)
 if (*p == '.')
   *p = '_';
*p = '\0';
if (*lastdot == '.')
 strncat (fname + i, lastdot, 4);
break;
    case 14:	/* old Unix systems with 14-char limitation */
strcpy (fname + i, orig);
if (strlen (fname + i) > 14)
 fname[i + 14] = '\0';
break;
    default:
strcpy (fname + i, orig);
if (strlen (fname) > maxlen - 1)
 fname[maxlen - 1] = '\0';
break;
  }

return fname;
621}
622
623/* Delayed writing functions.  A few of the commands
 needs to be handled at the end, namely @contents,
 @shortcontents, @printindex and @listoffloats.
 These functions take care of that.  */
627static DELAYED_WRITE *delayed_writes = NULL((void *)0);
628int handling_delayed_writes = 0;

630void
631register_delayed_write (char *delayed_command)
632{
DELAYED_WRITE *new;

if (!current_output_filename || !*current_output_filename)
  {
    /* Cannot register if we don't know what the output file is.  */
    warning (_("`%s' omitted before output filename")((const char *) ("`%s' omitted before output filename")), delayed_command);
    return;
  }

if (STREQ (current_output_filename, "-")(strcmp (current_output_filename, "-") == 0))
  {
    /* Do not register a new write if the output file is not seekable.
       Let the user know about it first, though.  */
    warning (_("`%s' omitted since writing to stdout")((const char *) ("`%s' omitted since writing to stdout")), delayed_command);
    return;
  }

/* Don't complain if the user is writing /dev/null, since surely they
   don't care, but don't register the delayed write, either.  */
if (FILENAME_CMPstrcmp (current_output_filename, NULL_DEVICE"/dev/null") == 0
    || FILENAME_CMPstrcmp (current_output_filename, ALSO_NULL_DEVICE"") == 0)
  return;
  
/* We need the HTML header in the output,
   to get a proper output_position.  */
if (!executing_string && html)
  html_output_head ();
/* Get output_position updated.  */
flush_output ();

new = xmalloc (sizeof (DELAYED_WRITE));
new->command = xstrdup (delayed_command);
new->filename = xstrdup (current_output_filename);
new->input_filename = xstrdup (input_filename);
new->position = output_position;
new->calling_line = line_number;
new->node = current_node ? xstrdup (current_node): "";

new->node_order = node_order;
new->index_order = index_counter;

new->next = delayed_writes;
delayed_writes = new;
676}

678void
679handle_delayed_writes (void)
680{
DELAYED_WRITE *temp = (DELAYED_WRITE *) reverse_list
  ((GENERIC_LIST *) delayed_writes);
int position_shift_amount, line_number_shift_amount;
char *delayed_buf;

handling_delayed_writes = 1;

while (temp)
  {
    delayed_buf = find_and_load (temp->filename, 0);

    if (output_paragraph_offset > 0)
      {
        error (_("Output buffer not empty.")((const char *) ("Output buffer not empty.")));
        return;
      }

    if (!delayed_buf)
      {
        fs_error (temp->filename);
        return;
      }

    output_stream = fopen (temp->filename, "w");
    if (!output_stream)
      {
        fs_error (temp->filename);
        return;
      }

    if (fwrite (delayed_buf, 1, temp->position, output_stream) != temp->position)
      {
        fs_error (temp->filename);
        return;
      }

    {
      int output_position_at_start = output_position;
      int line_number_at_start = output_line_number;

      /* In order to make warnings and errors
         refer to the correct line number.  */
      input_filename = temp->input_filename;
      line_number = temp->calling_line;

      execute_string ("%s", temp->command);
      flush_output ();

      /* Since the output file is modified, following delayed writes
         need to be updated by this amount.  */
      position_shift_amount = output_position - output_position_at_start;
      line_number_shift_amount = output_line_number - line_number_at_start;
    }

    if (fwrite (delayed_buf + temp->position, 1,
          input_text_length - temp->position, output_stream)
        != input_text_length - temp->position
        || fclose (output_stream) != 0)
      fs_error (temp->filename);

    /* Done with the buffer.  */
    free (delayed_buf);

    /* Update positions in tag table for nodes that are defined after
       the line this delayed write is registered.  */
    if (!html && !xml)
      {
        TAG_ENTRY *node;
        for (node = tag_table; node; node = node->next_ent)
          if (node->order > temp->node_order)
            node->position += position_shift_amount;
      }

    /* Something similar for the line numbers in all of the defined
       indices.  */
    {
      int i;
      for (i = 0; i < defined_indices; i++)
        if (name_index_alist[i])
          {
            char *name = ((INDEX_ALIST *) name_index_alist[i])->name;
            INDEX_ELT *index;
            for (index = index_list (name); index; index = index->next)
              if ((no_headers || STREQ (index->node, temp->node)(strcmp (index->node, temp->node) == 0))
                  && index->entry_number > temp->index_order)
                index->output_line += line_number_shift_amount;
          }
    }

    /* Shift remaining delayed positions
       by the length of this write.  */
    {
      DELAYED_WRITE *future_write = temp->next;
      while (future_write)
        {
          if (STREQ (temp->filename, future_write->filename)(strcmp (temp->filename, future_write->filename) == 0))
            future_write->position += position_shift_amount;
          future_write = future_write->next;
        }
    }

    temp = temp->next;
  }
784}