Change 'grub-mkrescue' to honor the 'GRUB_FAT_SERIAL_NUMBER'
environment variable.  That way, the caller can specify a fixed
serial number (instead of the randomly chosen one) to create EFI
images (the 'efi.img' file) that are reproducible bit-for-bit.

Patch by Ludovic Courtès <ludo@gnu.org>.
Mangled (for GRUB 2.04) by Tobias Geerinckx-Rice <me@tobias.gr>.

--- grub-2.04/util/grub-mkrescue.c	2019-05-20 13:01:11.000000000 +0200
+++ grub-2.04/util/grub-mkrescue.c	2019-07-08 23:57:36.912104652 +0200
@@ -809,8 +809,15 @@
       free (efidir_efi_boot);
 
       efiimgfat = grub_util_path_concat (2, iso9660_dir, "efi.img");
-      rv = grub_util_exec ((const char * []) { "mformat", "-C", "-f", "2880", "-L", "16", "-i",
-	    efiimgfat, "::", NULL });
+
+      const char *fat_serial_number = getenv ("GRUB_FAT_SERIAL_NUMBER");
+      const char *mformat_args[] =
+       { "mformat", "-C", "-f", "2880", "-L", "16",
+         fat_serial_number != NULL ? "-N" : "-C",
+         fat_serial_number != NULL ? fat_serial_number : "-C",
+         "-i", efiimgfat, "::", NULL };
+
+      rv = grub_util_exec (mformat_args);
       if (rv != 0)
 	grub_util_error ("`%s` invocation failed\n", "mformat");
       rv = grub_util_exec ((const char * []) { "mcopy", "-s", "-i", efiimgfat, efidir_efi, "::/", NULL });
e8997dc9756'>tree</a><a href='/guix/commit/.gitignore?id=b5e03030b0fd21bba86f1b5496ceee8997dc9756'>commit</a><a href='/guix/diff/.gitignore?id=b5e03030b0fd21bba86f1b5496ceee8997dc9756'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/.gitignore'>
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<div class='path'>path: <a href='/guix/log/?id=b5e03030b0fd21bba86f1b5496ceee8997dc9756&amp;showmsg=1'>root</a>/<a href='/guix/log/.gitignore?id=b5e03030b0fd21bba86f1b5496ceee8997dc9756&amp;showmsg=1'>.gitignore</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/.gitignore?id=b5e03030b0fd21bba86f1b5496ceee8997dc9756'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2023-10-22 20:35:15 -0400'>2023-10-22</span></td><td class='logsubject'><a href='/guix/commit/.gitignore?id=4cf4dcb8b31274a8dfba6bae3a6826a1b521da3f'>teams: Adjust shebang to use 'guix repl'.</a></td><td>Maxim Cournoyer</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
This ensures the correct Guix dependencies are always available for the
script.

* etc/teams.scm.in: Rename to...
* etc/teams.scm: ... this.  Adjust shebang.
* .gitignore: No longer ignore it.
* configure.ac: Do not process it with AC_CONFIG_FILES.

Reported-by: Clément Lassieur &lt;clement@lassieur.org&gt;
Fixes: https://issues.guix.gnu.org/66605
Change-Id: I7a01750c6c5f0696b6c36b1e6caa9389d9e6822c


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<tr class='logheader'><td><span title='2023-04-24 15:32:54 +0100'>2023-04-24</span></td><td class='logsubject'><a href='/guix/commit/.gitignore?id=23f11afacdfe755ffa514a8cbf93ba1121b9db0d'>Add mumi config.</a></td><td>Arun Isaac</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* .mumi/config: New file.
* .gitignore: Add .mumi/current-issue.


</td></tr>
<tr class='logheader'><td><span title='2022-07-03 14:12:32 +0200'>2022-07-03</span></td><td class='logsubject'><a href='/guix/commit/.gitignore?id=4eaf90470f466b3fdab87f6961cb18bb348d433f'>etc: Add teams.scm.</a></td><td>Ricardo Wurmus</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* etc/teams.scm.in: New file.
* configure.ac: Generate executable.
* .gitignore: Ignore generated file.


</td></tr>
<tr class='logheader'><td><span title='2022-06-05 21:27:53 +0200'>2022-06-05</span></td><td class='logsubject'><a href='/guix/commit/.gitignore?id=4d47c2c723927ad4ad4142bd517c6ccc03c27528'>gitignore: Add .DS_Store.</a></td><td>Pavel Shlyak</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
Ignore MacOS specific file: https://en.wikipedia.org/wiki/.DS_Store

Signed-off-by: Mathieu Othacehe &lt;othacehe@gnu.org&gt;


</td></tr>