[Qemu-devel] [PATCH 1/2] Rework -boot option

[Jan Kiszka <jan.kiszka@siemens.com>]

This patch changes the boot command line option to the canonical format

 -boot [order=drives][,interactive=on|off]

where 'drives' is using the same format as the old -boot. The new format
is required in order to add the 'interactive' option and use the
existing infrastructure to parse it.

The state of 'interactive' is transfered to the firmware via the new
configuration value FW_CFG_BOOT_INTERACTIVE.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---

 hw/fw_cfg.c     |    1 +
 hw/fw_cfg.h     |    1 +
 qemu-options.hx |   19 ++++++++++---
 sysemu.h        |    1 +
 vl.c            |   80 +++++++++++++++++++++++++++++++++++++------------------
 5 files changed, 72 insertions(+), 30 deletions(-)

diff --git a/hw/fw_cfg.c b/hw/fw_cfg.c
index e1b19d7..c21cdb3 100644
--- a/hw/fw_cfg.c
+++ b/hw/fw_cfg.c
@@ -279,6 +279,7 @@ void *fw_cfg_init(uint32_t ctl_port, uint32_t data_port,
     fw_cfg_add_bytes(s, FW_CFG_UUID, qemu_uuid, 16);
     fw_cfg_add_i16(s, FW_CFG_NOGRAPHIC, (uint16_t)nographic);
     fw_cfg_add_i16(s, FW_CFG_NB_CPUS, (uint16_t)smp_cpus);
+    fw_cfg_add_i16(s, FW_CFG_BOOT_INTERACTIVE, (uint16_t)boot_interactive);
 
     register_savevm("fw_cfg", -1, 1, fw_cfg_save, fw_cfg_load, s);
     qemu_register_reset(fw_cfg_reset, s);
diff --git a/hw/fw_cfg.h b/hw/fw_cfg.h
index 41a3dd0..131dbf2 100644
--- a/hw/fw_cfg.h
+++ b/hw/fw_cfg.h
@@ -14,6 +14,7 @@
 #define FW_CFG_INITRD_ADDR      0x0a
 #define FW_CFG_INITRD_SIZE      0x0b
 #define FW_CFG_BOOT_DEVICE      0x0c
+#define FW_CFG_BOOT_INTERACTIVE 0x0d
 #define FW_CFG_MAX_ENTRY        0x10
 
 #define FW_CFG_WRITE_CHANNEL    0x4000
diff --git a/qemu-options.hx b/qemu-options.hx
index 4d15f9b..4cfe199 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -210,11 +210,22 @@ Use 'file' as a parallel flash image.
 ETEXI
 
 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
-    "-boot [a|c|d|n] boot on floppy (a), hard disk (c), CD-ROM (d), or network (n)\n")
+    "-boot [order=drives][,interactive=on|off]\n"
+    "                'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n")
 STEXI
-@item -boot [a|c|d|n]
-Boot on floppy (a), hard disk (c), CD-ROM (d), or Etherboot (n). Hard disk boot
-is the default.
+@item -boot [order=@var{drives}][,interactive=on|off]
+
+Specify boot order @var{drives} as a string of drive letters. Valid
+drive letters depend on the target achitecture. The x86 PC uses: a, b
+(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
+from network adapter 1-4), hard disk boot is the default. Furthermore,
+interactive boot menus/prompts can be enabled as far as firmware/BIOS
+supports them. The default is non-interactive boot.
+
+@example
+# try to boot from network first, then from hard disk
+qemu -boot order=nc
+@end example
 ETEXI
 
 DEF("snapshot", 0, QEMU_OPTION_snapshot,
diff --git a/sysemu.h b/sysemu.h
index 2b1677c..5aed865 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -103,6 +103,7 @@ extern int graphic_rotate;
 extern int no_quit;
 extern int semihosting_enabled;
 extern int old_param;
+extern int boot_interactive;
 
 #ifdef USE_KQEMU
 extern int kqemu_allowed;
diff --git a/vl.c b/vl.c
index 72ea0e4..5b2f2c8 100644
--- a/vl.c
+++ b/vl.c
@@ -264,6 +264,7 @@ const char *prom_envs[MAX_PROM_ENVS];
 #endif
 int nb_drives_opt;
 struct drive_opt drives_opt[MAX_DRIVES];
+int boot_interactive;
 
 static CPUState *cur_cpu;
 static CPUState *next_cpu;
@@ -4254,7 +4255,7 @@ int main(int argc, char **argv, char **envp)
     int snapshot, linux_boot, net_boot;
     const char *initrd_filename;
     const char *kernel_filename, *kernel_cmdline;
-    const char *boot_devices = "";
+    char boot_devices[33] = "";
     DisplayState *ds;
     DisplayChangeListener *dcl;
     int cyls, heads, secs, translation;
@@ -4529,33 +4530,60 @@ int main(int argc, char **argv, char **envp)
                 drive_add(optarg, CDROM_ALIAS);
                 break;
             case QEMU_OPTION_boot:
-                boot_devices = optarg;
-                /* We just do some generic consistency checks */
                 {
-                    /* Could easily be extended to 64 devices if needed */
-                    const char *p;
-                    
-                    boot_devices_bitmap = 0;
-                    for (p = boot_devices; *p != '\0'; p++) {
-                        /* Allowed boot devices are:
-                         * a b     : floppy disk drives
-                         * c ... f : IDE disk drives
-                         * g ... m : machine implementation dependant drives
-                         * n ... p : network devices
-                         * It's up to each machine implementation to check
-                         * if the given boot devices match the actual hardware
-                         * implementation and firmware features.
-                         */
-                        if (*p < 'a' || *p > 'q') {
-                            fprintf(stderr, "Invalid boot device '%c'\n", *p);
-                            exit(1);
+                    static const char * const params[] = {
+                        "order", "interactive", NULL
+                    };
+                    char buf[16];
+
+                    if (check_params(buf, sizeof(buf), params, optarg) < 0) {
+                        fprintf(stderr,
+                                "qemu: unknown boot parameter '%s' in '%s'\n",
+                                buf, optarg);
+                        exit(1);
+                    }
+
+                    if (get_param_value(boot_devices, sizeof(boot_devices),
+                                        "order", optarg)) {
+                        /* We just do some generic consistency checks */
+                        const char *p;
+
+                        boot_devices_bitmap = 0;
+                        for (p = boot_devices; *p != '\0'; p++) {
+                            /* Allowed boot devices are:
+                             * a-b: floppy disk drives
+                             * c-f: IDE disk drives
+                             * g-m: machine implementation dependant drives
+                             * n-p: network devices
+                             * It's up to each machine implementation to check
+                             * if the given boot devices match the actual
+                             * hardware implementation and firmware features.
+                             */
+                            if (*p < 'a' || *p > 'p') {
+                                fprintf(stderr, "Invalid boot device '%c'\n",
+                                        *p);
+                                exit(1);
+                            }
+                            if (boot_devices_bitmap & (1 << (*p - 'a'))) {
+                                fprintf(stderr,
+                                        "Boot device '%c' was given twice\n",
+                                        *p);
+                                exit(1);
+                             }
+                             boot_devices_bitmap |= 1 << (*p - 'a');
                         }
-                        if (boot_devices_bitmap & (1 << (*p - 'a'))) {
-                            fprintf(stderr,
-                                    "Boot device '%c' was given twice\n",*p);
-                            exit(1);
+                    }
+                    if (get_param_value(buf, sizeof(buf), "interactive",
+                                        optarg)) {
+                        if (!strcmp(buf, "on")) {
+                            boot_interactive = 1;
+                        } else if (!strcmp(buf, "off")) {
+                            boot_interactive = 0;
+                        } else {
+                           fprintf(stderr,
+                                   "qemu: invalid option value '%s'\n", buf);
+                           exit(1);
                         }
-                        boot_devices_bitmap |= 1 << (*p - 'a');
                     }
                 }
                 break;
@@ -5074,7 +5102,7 @@ int main(int argc, char **argv, char **envp)
 
     /* boot to floppy or the default cd if no hard disk defined yet */
     if (!boot_devices[0]) {
-        boot_devices = "cad";
+        strcpy(boot_devices, "cad");
     }
     setvbuf(stdout, NULL, _IOLBF, 0);