src/hci/strerror.c

   1 #include <errno.h>
   2 #include <string.h>
   3 #include <stdio.h>
   4 #include <gpxe/errortab.h>
   5
   6 /** @file
   7  *
   8  * Error descriptions.
   9  *
  10  * The error numbers used by Etherboot are a superset of those defined
  11  * by the PXE specification version 2.1.  See errno.h for a listing of
  12  * the error values.
  13  *
  14  * To save space in ROM images, error string tables are optional.  Use
  15  * the ERRORMSG_XXX options in config.h to select which error string
  16  * tables you want to include.  If an error string table is omitted,
  17  * strerror() will simply return the text "Error 0x<errno>".
  18  *
  19  */
  20
  21 FILE_LICENCE ( GPL2_OR_LATER );
  22
  23 /**
  24  * Find error description
  25  *
  26  * @v errno             Error number
  27  * @ret errortab        Error description, or NULL
  28  */
  29 static struct errortab * find_error ( int errno ) {
  30         struct errortab *errortab;
  31
  32         for_each_table_entry ( errortab, ERRORTAB ) {
  33                 if ( errortab->errno == errno )
  34                         return errortab;
  35         }
  36
  37         return NULL;
  38 }
  39
  40 /**
  41  * Find closest error description
  42  *
  43  * @v errno             Error number
  44  * @ret errortab        Error description, or NULL
  45  *
  46  *
  47  */
  48 static struct errortab * find_closest_error ( int errno ) {
  49         struct errortab *errortab;
  50
  51         /* First, look for an exact match */
  52         if ( ( errortab = find_error ( errno ) ) != NULL )
  53                 return errortab;
  54
  55         /* Second, try masking off the gPXE-specific bit and seeing if
  56          * we have an entry for the generic POSIX error message.
  57          */
  58         if ( ( errortab = find_error ( errno & 0x7f0000ff ) ) != NULL )
  59                 return errortab;
  60
  61         return NULL;
  62 }
  63
  64 /**
  65  * Retrieve string representation of error number.
  66  *
  67  * @v errno/rc          Error number or return status code
  68  * @ret strerror        Pointer to error text
  69  *
  70  * If the error is not found in the linked-in error tables, generates
  71  * a generic "Error 0x<errno>" message.
  72  *
  73  * The pointer returned by strerror() is valid only until the next
  74  * call to strerror().
  75  *
  76  */
  77 const char * strerror ( int errno ) {
  78         static char errbuf[64];
  79         struct errortab *errortab;
  80
  81         /* Allow for strerror(rc) as well as strerror(errno) */
  82         if ( errno < 0 )
  83                 errno = -errno;
  84
  85         /* Find the error description, if one exists */
  86         errortab = find_closest_error ( errno );
  87
  88         /* Construct the error message */
  89         if ( errortab ) {
  90                 snprintf ( errbuf, sizeof ( errbuf ), "%s (%#08x)",
  91                            errortab->text, errno );
  92         } else {
  93                 snprintf ( errbuf, sizeof ( errbuf ), "Error %#08x", errno );
  94         }
  95
  96         return errbuf;
  97 }
  98
  99 /* Do not include ERRFILE portion in the numbers in the error table */
 100 #undef ERRFILE
 101 #define ERRFILE 0
 102
 103 /** The most common errors */
 104 struct errortab common_errors[] __errortab = {
 105         __einfo_errortab ( EINFO_ENOERR ),
 106         __einfo_errortab ( EINFO_EACCES ),
 107         __einfo_errortab ( EINFO_ECANCELED ),
 108         __einfo_errortab ( EINFO_ECONNRESET ),
 109         __einfo_errortab ( EINFO_EINVAL ),
 110         __einfo_errortab ( EINFO_EIO ),
 111         __einfo_errortab ( EINFO_ENETUNREACH ),
 112         __einfo_errortab ( EINFO_ENODEV ),
 113         __einfo_errortab ( EINFO_ENOENT ),
 114         __einfo_errortab ( EINFO_ENOEXEC ),
 115         __einfo_errortab ( EINFO_ENOMEM ),
 116         __einfo_errortab ( EINFO_ENOSPC ),
 117         __einfo_errortab ( EINFO_ENOTCONN ),
 118         __einfo_errortab ( EINFO_ENOTSUP ),
 119         __einfo_errortab ( EINFO_EPERM ),
 120         __einfo_errortab ( EINFO_ERANGE ),
 121         __einfo_errortab ( EINFO_ETIMEDOUT ),
 122 };