usershell.c 4.0 KB

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  1. /*
  2. * Copyright (c) 1985, 1993
  3. * The Regents of the University of California. All rights reserved.
  4. *
  5. * Redistribution and use in source and binary forms, with or without
  6. * modification, are permitted provided that the following conditions
  7. * are met:
  8. * 1. Redistributions of source code must retain the above copyright
  9. * notice, this list of conditions and the following disclaimer.
  10. * 2. Redistributions in binary form must reproduce the above copyright
  11. * notice, this list of conditions and the following disclaimer in the
  12. * documentation and/or other materials provided with the distribution.
  13. * 4. Neither the name of the University nor the names of its contributors
  14. * may be used to endorse or promote products derived from this software
  15. * without specific prior written permission.
  16. *
  17. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27. * SUCH DAMAGE.
  28. *
  29. * This version has been hevily modified for use with uClibc
  30. * November 2002, Erik Andersen <andersen@codepoet.org>
  31. */
  32. #include <sys/param.h>
  33. #include <sys/file.h>
  34. #include <sys/stat.h>
  35. #include <stdio.h>
  36. #include <stdio_ext.h>
  37. #include <ctype.h>
  38. #include <stdlib.h>
  39. #include <unistd.h>
  40. #include <paths.h>
  41. libc_hidden_proto(fstat)
  42. libc_hidden_proto(fopen)
  43. libc_hidden_proto(fclose)
  44. libc_hidden_proto(__fsetlocking)
  45. libc_hidden_proto(fileno)
  46. libc_hidden_proto(fgets_unlocked)
  47. #ifdef __UCLIBC_HAS_XLOCALE__
  48. libc_hidden_proto(__ctype_b_loc)
  49. #else
  50. libc_hidden_proto(__ctype_b)
  51. #endif
  52. /*
  53. * Local shells should NOT be added here. They should be added in
  54. * /etc/shells.
  55. */
  56. static const char * const validsh[] = { _PATH_BSHELL, _PATH_CSHELL, NULL };
  57. static char **curshell, **shells, *strings;
  58. static char **initshells __P((void));
  59. /*
  60. * Get a list of shells from _PATH_SHELLS, if it exists.
  61. */
  62. char * getusershell(void)
  63. {
  64. char *ret;
  65. if (curshell == NULL)
  66. curshell = initshells();
  67. ret = *curshell;
  68. if (ret != NULL)
  69. curshell++;
  70. return (ret);
  71. }
  72. static void __free_initshell_memory(void)
  73. {
  74. if (shells != NULL) {
  75. free(shells);
  76. }
  77. shells = NULL;
  78. if (strings != NULL) {
  79. free(strings);
  80. }
  81. strings = NULL;
  82. }
  83. void endusershell(void)
  84. {
  85. __free_initshell_memory();
  86. curshell = NULL;
  87. }
  88. void setusershell(void)
  89. {
  90. curshell = initshells();
  91. }
  92. static char ** initshells(void)
  93. {
  94. register char **sp, *cp;
  95. register FILE *fp;
  96. struct stat statb;
  97. int flen;
  98. __free_initshell_memory();
  99. if ((fp = fopen(_PATH_SHELLS, "r")) == NULL)
  100. return (char **) validsh;
  101. if (fstat(fileno(fp), &statb) == -1) {
  102. goto cleanup;
  103. }
  104. if ((strings = malloc((unsigned)statb.st_size + 1)) == NULL) {
  105. goto cleanup;
  106. }
  107. if ((shells = calloc((unsigned)statb.st_size / 3, sizeof (char *))) == NULL) {
  108. goto cleanup;
  109. }
  110. /* No threads using this stream. */
  111. #ifdef __UCLIBC_HAS_THREADS__
  112. __fsetlocking (fp, FSETLOCKING_BYCALLER);
  113. #endif
  114. sp = shells;
  115. cp = strings;
  116. flen = statb.st_size;
  117. while (fgets_unlocked(cp, flen - (cp - strings), fp) != NULL) {
  118. while (*cp != '#' && *cp != '/' && *cp != '\0')
  119. cp++;
  120. if (*cp == '#' || *cp == '\0')
  121. continue;
  122. *sp++ = cp;
  123. while (!isspace(*cp) && *cp != '#' && *cp != '\0')
  124. cp++;
  125. *cp++ = '\0';
  126. }
  127. *sp = NULL;
  128. fclose(fp);
  129. return (shells);
  130. cleanup:
  131. __free_initshell_memory();
  132. fclose(fp);
  133. return (char **) validsh;
  134. }