source: clfs-sysroot/BOOK/cross-tools/common/sysroot_wrapper.xml @ 12e6567

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
  "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../../general.ent">
  %general-entities;
]>

<sect1 id="ch-cross-tools-sysroot-wrapper" role="wrap">
  <?dbhtml filename="sysroot_wrapper.html"?>

  <title>Creating a Sysroot Wrapper</title>

  <indexterm zone="ch-cross-tools-sysroot-wrapper">
    <primary sortas="a-File">Sysroot Wrapper</primary>
  </indexterm>

  <sect2 role="package">
    <title/>

    <para>The Sysroot Wrapper is used to wrap certain binaries that have
    hardcoded paths to libraries or are architecture specific.</para>

  </sect2>

  <sect2 role="installation">
    <title>Installation of The Sysroot Wrapper</title>

    <para os="a">Create the source file:</para>

<screen os="b"><userinput>cat &gt; sysroot_wrapper.c &lt;&lt; "EOF"
#include &lt;sys/wait.h&gt;
#include &lt;stdio.h&gt;
#include &lt;stdlib.h&gt;
#include &lt;unistd.h&gt;
#include &lt;string.h&gt;

char *sysrootdir = "";

int main(int argc, char *argv[]) {
  sysrootdir = getenv("CLFS");
  if (!sysrootdir)
    sysrootdir="";

  int stdout_pipe[2];
  pipe(stdout_pipe);

  pid_t pid = fork();

  if (pid == 0) {
    /* Redirect stdout to our pipe */
    close(1);
    dup(stdout_pipe[1]);
    close(stdout_pipe[0]);
    close(stdout_pipe[1]);

    char *name = strdup(argv[0]);
    strcat(name, ".sysroot");

    execvp(name, argv);

    free(name);

    exit(0);
  } else {
    /* Close stdout for write */
    close(stdout_pipe[1]);

    /* redirect our stdout pipe from the child to our stdin */
    close(0);
    dup(stdout_pipe[0]);
    close(stdout_pipe[0]);

    char c, lc;
    char *d = malloc(1);
    int d_len = 0;

    while ((c = fgetc(stdin)) != EOF) {
      d_len++;
      d = realloc(d, d_len + 1);
      *(d + d_len - 1) = c;
      *(d + d_len) = '\0';

      if ((lc == '-')&amp;&amp;((c == 'L')||(c == 'I'))) {
        d_len = d_len + strlen(sysrootdir);
        d = realloc(d, d_len + 1);
        strcat(d, sysrootdir);
      }

      lc = c;
    }

    printf ("%s", d);
    free(d);

    exit(0);
  }

  return 0;
}
EOF</userinput></screen>

    <para os="c">Compile and Install the Sysroot Wrapper:</para>

<screen os="d"><userinput>gcc ${BUILD64} sysroot_wrapper.c -o ${CLFS}/cross-tools/bin/sysroot_wrapper</userinput></screen>

  </sect2>

  <sect2 id="contents-sysroot-wrapper" role="content">
    <title>Contents of The Sysroot Wrapper</title>

    <segmentedlist>
      <segtitle>Installed programs</segtitle>

      <seglistitem>
        <seg>sysroot_wrapper</seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="sysroot_wrapper">
        <term><command>sysroot_wrapper</command></term>
        <listitem>
          <para>Description Needed</para>
          <indexterm zone="ch-cross-tools-sysroot-wrapper sysroot_wrapper">
            <primary sortas="b-sysroot_wrapper">sysroot_wrapper</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>