stage2/kbootconf.c

   1 /*  kbootcfg.c - kboot.cfg parsing
   2
   3 Copyright (C) 2010-2011  Hector Martin "marcan" <hector@marcansoft.com>
   4
   5 This code is licensed to you under the terms of the GNU GPL, version 2;
   6 see file COPYING or http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
   7 */
   8
   9 /* See http://www.kernel.org/pub/linux/kernel/people/geoff/cell/ps3-linux-docs/ps3-linux-docs-08.06.09/mini-boot-conf.txt */
  10
  11 #include "types.h"
  12 #include "string.h"
  13 #include "kbootconf.h"
  14 #include "debug.h"
  15
  16 char conf_buf[MAX_KBOOTCONF_SIZE];
  17
  18 struct kbootconf conf;
  19
  20 char *strip(char *buf)
  21 {
  22         while (*buf == ' ' || *buf == '\t')
  23                 buf++;
  24         char *end = buf + strlen(buf) - 1;
  25         while (*end == ' ' || *end == '\t')
  26                 *end-- = 0;
  27
  28         return buf;
  29 }
  30
  31 void split(char *buf, char **left, char **right, char delim)
  32 {
  33         char *p = strchr(buf, delim);
  34
  35         if (p) {
  36                 *p = 0;
  37                 *left = strip(buf);
  38                 *right = strip(p+1);
  39         } else {
  40                 *left = strip(buf);
  41                 *right = NULL;
  42         }
  43 }
  44
  45 int kbootconf_parse(void)
  46 {
  47         char *lp = conf_buf;
  48         char *dflt = NULL;
  49         char *dinitrd = NULL;
  50         char *droot = NULL;
  51         char tmpbuf[MAX_CMDLINE_SIZE];
  52         int lineno = 1;
  53         int i;
  54
  55         memset(&conf, 0, sizeof(conf));
  56
  57         conf.timeout = -1;
  58
  59         while(*lp) {
  60                 char *newline = strchr(lp, '\n');
  61                 char *next;
  62                 if (newline) {
  63                         *newline = 0;
  64                         next = newline+1;
  65                 } else {
  66                         next = lp+strlen(lp);
  67                 }
  68
  69                 lp = strip(lp);
  70                 if (!*lp)
  71                         goto nextline;
  72
  73                 char *left, *right;
  74
  75                 split(lp, &left, &right, '=');
  76                 if (!right) {
  77                         printf("kboot.conf: parse error (line %d)\n", lineno);
  78                         goto nextline;
  79                 }
  80
  81                 while(*right == '"' || *right == '\'')
  82                         right++;
  83                 char *rend = right + strlen(right) - 1;
  84                 while(*rend == '"' || *rend == '\'')
  85                         *rend-- = 0;
  86
  87                 if (!strcmp(left, "timeout")) {
  88                         conf.timeout = my_atoi(right);
  89                 } else if (!strcmp(left, "default")) {
  90                         dflt = right;
  91                 } else if (!strcmp(left, "message")) {
  92                         conf.msgfile = right;
  93                 } else if (!strcmp(left, "initrd")) {
  94                         dinitrd = right;
  95                 } else if (!strcmp(left, "root")) {
  96                         droot = right;
  97                 } else if (!strcmp(left, "video")) {
  98                         // TODO: use
  99                 } else {
 100                         if (strlen(right) > MAX_CMDLINE_SIZE) {
 101                                 printf("kboot.conf: maximum length exceeded (line %d)\n", lineno);
 102                                 goto nextline;
 103                         }
 104                         conf.kernels[conf.num_kernels].label = left;
 105                         conf.kernels[conf.num_kernels].kernel = right;
 106                         char *p = strchr(right, ' ');
 107                         if (!p) {
 108                                 // kernel, no arguments
 109                                 conf.num_kernels++;
 110                                 goto nextline;
 111                         }
 112                         *p++ = 0;
 113                         char *buf = p;
 114                         char *root = NULL;
 115                         char *initrd = NULL;
 116                         tmpbuf[0] = 0;
 117                         /* split commandline arguments and extract the useful bits */
 118                         while (*p) {
 119                                 char *spc = strchr(p, ' ');
 120                                 if (spc)
 121                                         *spc++ = 0;
 122                                 else
 123                                         spc = p+strlen(p);
 124                                 if (*p == 0) {
 125                                         p = spc;
 126                                         continue;
 127                                 }
 128
 129                                 char *arg, *val;
 130                                 split(p, &arg, &val, '=');
 131                                 if (!val) {
 132                                         strlcat(tmpbuf, arg, sizeof(tmpbuf));
 133                                         strlcat(tmpbuf, " ", sizeof(tmpbuf));
 134                                 } else if (!strcmp(arg, "root")) {
 135                                         root = val;
 136                                 } else if (!strcmp(arg, "initrd")) {
 137                                         initrd = val;
 138                                 } else {
 139                                         strlcat(tmpbuf, arg, sizeof(tmpbuf));
 140                                         strlcat(tmpbuf, "=", sizeof(tmpbuf));
 141                                         strlcat(tmpbuf, val, sizeof(tmpbuf));
 142                                         strlcat(tmpbuf, " ", sizeof(tmpbuf));
 143                                 }
 144
 145                                 p = spc;
 146                         }
 147
 148                         int len = strlen(tmpbuf);
 149                         if (len && tmpbuf[len-1] == ' ')
 150                                 tmpbuf[--len] = 0;
 151                         len++;
 152
 153                         // UGLY: tack on initrd and root onto tmpbuf, then copy it entirely
 154                         // on top of the original buffer (avoids having to deal with malloc)
 155                         conf.kernels[conf.num_kernels].parameters = buf;
 156                         if (initrd) {
 157                                 strlcpy(tmpbuf+len, initrd, sizeof(tmpbuf)-len);
 158                                 conf.kernels[conf.num_kernels].initrd = buf + len;
 159                                 len += strlen(initrd)+1;
 160                         }
 161                         if (root) {
 162                                 strlcpy(tmpbuf+len, root, sizeof(tmpbuf)-len);
 163                                 conf.kernels[conf.num_kernels].root = buf + len;
 164                                 len += strlen(root)+1;
 165                         }
 166                         memcpy(buf, tmpbuf, len);
 167                         conf.num_kernels++;
 168                 }
 169
 170 nextline:
 171                 lp = next;
 172                 lineno++;
 173         }
 174
 175         conf.default_idx = 0;
 176         for (i=0; i<conf.num_kernels; i++) {
 177                 if (dflt && !strcmp(conf.kernels[i].label, dflt))
 178                         conf.default_idx = i;
 179                 if (!conf.kernels[i].initrd && dinitrd)
 180                         conf.kernels[i].initrd = dinitrd;
 181                 if (!conf.kernels[i].root && droot)
 182                         conf.kernels[i].root = droot;
 183                 if (conf.kernels[i].initrd && !conf.kernels[i].root)
 184                         conf.kernels[i].root = "/dev/ram0";
 185         }
 186
 187         printf("==== kboot.conf dump ====\n");
 188         if (conf.timeout != -1)
 189                 printf("Timeout: %d\n", conf.timeout);
 190         if (conf.msgfile)
 191                 printf("Message: %s\n", conf.msgfile);
 192
 193         for (i=0; i<conf.num_kernels; i++) {
 194                 printf("Entry #%d '%s'", i, conf.kernels[i].label);
 195                 if (conf.default_idx == i)
 196                         printf(" (default):\n");
 197                 else
 198                         printf(":\n");
 199                 printf(" Kernel: %s\n", conf.kernels[i].kernel);
 200                 if (conf.kernels[i].initrd)
 201                         printf(" Initrd: %s\n", conf.kernels[i].initrd);
 202                 if (conf.kernels[i].root)
 203                         printf(" Root: %s\n", conf.kernels[i].root);
 204                 if (conf.kernels[i].parameters)
 205                         printf(" Parameters: %s\n", conf.kernels[i].parameters);
 206         }
 207
 208         printf("=========================\n");
 209         return conf.num_kernels;
 210 }