[PATCH 2/2] pci-arbiter: Add --device command line option

[Joan Lledó]

From: Joan Lledó <jlledom@member.fsf.org>

Shortcut for -d, -b, -s and -f
Usage: --device [<domain>:]<bus>:<slot>.<func>
E.G. --device 00:05.0 is shortcut for -d 0 -b 0 -s 5 -f 0

* pci-arbiter/options.c: Implement --slot option
* pci-arbiter/options.h: Add --slot to options list
---
 pci-arbiter/options.c | 57 +++++++++++++++++++++++++++++++++++++++++++
 pci-arbiter/options.h |  2 ++
 2 files changed, 59 insertions(+)

diff --git a/pci-arbiter/options.c b/pci-arbiter/options.c
index 01686fcd..2023fd9e 100644
--- a/pci-arbiter/options.c
+++ b/pci-arbiter/options.c
@@ -27,9 +27,13 @@
 #include <argp.h>
 #include <argz.h>
 #include <error.h>
+#include <regex.h>
 
 #include "pcifs.h"
 
+#define PCI_SLOT_REGEX 
"^(([0-9a-fA-F]{4}):)?([0-9a-fA-F]{2}):([0-9a-fA-F]{2})\\.([0-7])$"
+#define PCI_SLOT_REGEX_GROUPS 6        // 2: Domain, 3: Bus, 4: Dev, 5: Func
+
 /* Fsysopts and command line option parsing */
 
 /* Adds an empty interface slot to H, and sets H's current interface to it, or
@@ -91,6 +95,9 @@ parse_opt (int opt, char *arg, struct argp_state *state)
 {
   error_t err = 0;
   struct parse_hook *h = state->hook;
+  regex_t slot_regex;
+  regmatch_t slot_regex_groups[PCI_SLOT_REGEX_GROUPS];
+  char regex_group_val[5];
 
   /* Return _ERR from this routine */
 #define RETURN(_err)                          \
@@ -111,6 +118,11 @@ parse_opt (int opt, char *arg, struct argp_state *state)
       state->next++;
     }
 
+  /* Compile regular expression to check --slot option */
+  err = regcomp (&slot_regex, PCI_SLOT_REGEX, REG_EXTENDED);
+  if (err)
+    FAIL (err, 1, err, "option parsing");
+
   switch (opt)
     {
     case 'C':
@@ -134,6 +146,48 @@ parse_opt (int opt, char *arg, struct argp_state *state)
     case 'f':
       h->curset->func = strtol (arg, 0, 16);
       break;
+    case 'D':
+      err =
+       regexec (&slot_regex, arg, PCI_SLOT_REGEX_GROUPS, slot_regex_groups,
+                0);
+      if (!err)
+       {
+         // Domain, 0000 by default
+         if (slot_regex_groups[2].rm_so >= 0)
+           {
+             strncpy (regex_group_val, arg + slot_regex_groups[2].rm_so, 4);
+             regex_group_val[4] = 0;
+           }
+         else
+           {
+             strncpy (regex_group_val, "0000", 5);
+           }
+
+         h->curset->domain = strtol (regex_group_val, 0, 16);
+
+         // Bus
+         strncpy (regex_group_val, arg + slot_regex_groups[3].rm_so, 2);
+         regex_group_val[2] = 0;
+
+         h->curset->bus = strtol (regex_group_val, 0, 16);
+
+         // Dev
+         strncpy (regex_group_val, arg + slot_regex_groups[4].rm_so, 2);
+         regex_group_val[2] = 0;
+
+         h->curset->dev = strtol (regex_group_val, 0, 16);
+
+         // Func
+         regex_group_val[0] = arg[slot_regex_groups[5].rm_so];
+         regex_group_val[1] = 0;
+
+         h->curset->func = strtol (regex_group_val, 0, 16);
+       }
+      else
+       {
+         PERR (err, "Wrong PCI slot. Format: [<domain>:]<bus>:<dev>.<func>");
+       }
+      break;
     case 'U':
       if (h->curset->uid >= 0)
        parse_hook_add_set (h);
@@ -227,6 +281,9 @@ parse_opt (int opt, char *arg, struct argp_state *state)
       return ARGP_ERR_UNKNOWN;
     }
 
+  /* Free allocated regular expression for the --slot option */
+  regfree (&slot_regex);
+
   return err;
 }
 
diff --git a/pci-arbiter/options.h b/pci-arbiter/options.h
index 9a25c603..8e5a9da4 100644
--- a/pci-arbiter/options.h
+++ b/pci-arbiter/options.h
@@ -57,6 +57,8 @@ static const struct argp_option options[] = {
   {"bus", 'b', "BUS", 0, "Device bus in hexadecimal"},
   {"slot", 's', "SLOT", 0, "Device slot in hexadecimal, requires -b"},
   {"func", 'f', "FUNC", 0, "Device func in hexadecimal, requires -s"},
+  {"device", 'D', "DEVICE", 0,
+   "Device address in format [<domain>:]<bus>:<slot>.<func>"},
   {0, 0, 0, 0, "These apply to a given permission scope:", 2},
   {"uid", 'U', "UID", 0, "User ID to give permissions to"},
   {"gid", 'G', "GID", 0, "Group ID to give permissions to"},
-- 
2.20.1