From c27e69116d3ef0ea069a3c5146009ced08a0238b Mon Sep 17 00:00:00 2001 From: "patmans@us.ibm.com" Date: Tue, 14 Oct 2003 23:32:17 -0700 Subject: [PATCH] [PATCH] add callout config type to udev This patch adds a callout config type to udev, so external programs can be called to get serial numbers or id's that are not available as a sysfs attribute. --- namedev.c | 132 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ namedev.h | 2 + udev.c | 8 +++- udev.h | 2 + 4 files changed, 143 insertions(+), 1 deletion(-) diff --git a/namedev.c b/namedev.c index 782b73d0..abed8685 100644 --- a/namedev.c +++ b/namedev.c @@ -31,6 +31,7 @@ #include #include #include +#include #include "list.h" #include "udev.h" @@ -42,6 +43,7 @@ #define TYPE_NUMBER "NUMBER" #define TYPE_TOPOLOGY "TOPOLOGY" #define TYPE_REPLACE "REPLACE" +#define TYPE_CALLOUT "CALLOUT" static LIST_HEAD(config_device_list); @@ -78,6 +80,12 @@ static void dump_dev(struct config_device *dev) dev->attr.name, dev->kernel_name, dev->attr.owner, dev->attr.group, dev->attr.mode); break; + case CALLOUT: + dbg("CALLOUT name = '%s', program ='%s', bus = '%s', id = '%s'" + " owner = '%s', group = '%s', mode = '%#o'", + dev->attr.name, dev->exec_program, dev->bus, dev->id, + dev->attr.owner, dev->attr.group, dev->attr.mode); + break; default: dbg("Unknown type of device!"); } @@ -330,6 +338,38 @@ static int namedev_init_config(void) strcpy(dev.attr.name, temp3); dbg("REPLACE name = %s, kernel_name = %s", dev.attr.name, dev.kernel_name); } + if (strcasecmp(temp2, TYPE_CALLOUT) == 0) { + /* number type */ + dev.type = CALLOUT; + + /* PROGRAM="executable" */ + retval = get_value("PROGRAM", &temp, &temp3); + if (retval) + continue; + strcpy(dev.exec_program, temp3); + + /* BUS="bus" */ + temp2 = strsep(&temp, ","); + retval = get_value("BUS", &temp, &temp3); + if (retval) + continue; + strcpy(dev.bus, temp3); + + /* ID="id" */ + temp2 = strsep(&temp, ","); + retval = get_value("ID", &temp, &temp3); + if (retval) + continue; + strcpy(dev.id, temp3); + + /* NAME="new_name" */ + temp2 = strsep(&temp, ","); + retval = get_value("NAME", &temp, &temp3); + if (retval) + continue; + strcpy(dev.attr.name, temp3); + dbg("CALLOUT name = %s, program = %s", dev.attr.name, dev.exec_program); + } retval = add_dev(&dev); if (retval) { @@ -417,6 +457,78 @@ static int get_default_mode(struct sysfs_class_device *class_dev) } +static int exec_callout(struct config_device *dev, char *value, int len) +{ + int retval; + int res; + int status; + int fds[2]; + pid_t pid; + int value_set = 0; + char buffer[256]; + + dbg("callout to %s\n", dev->exec_program); + retval = pipe(fds); + if (retval != 0) { + dbg("pipe failed"); + return -1; + } + pid = fork(); + if (pid == -1) { + dbg("fork failed"); + return -1; + } + + if (pid == 0) { + /* + * child + */ + close(STDOUT_FILENO); + dup(fds[1]); /* dup write side of pipe to STDOUT */ + retval = execve(dev->exec_program, main_argv, main_envp); + if (retval != 0) { + dbg("child execve failed"); + exit(1); + } + return -1; /* avoid compiler warning */ + } else { + /* + * Parent reads from fds[0]. + */ + close(fds[1]); + retval = 0; + while (1) { + res = read(fds[0], buffer, sizeof(buffer) - 1); + if (res <= 0) + break; + buffer[res] = '\0'; + if (res > len) { + dbg("callout len %d too short\n", len); + retval = -1; + } + if (value_set) { + dbg("callout value already set"); + retval = -1; + } else { + value_set = 1; + strncpy(value, buffer, len); + } + } + close(fds[0]); + res = wait(&status); + if (res < 0) { + dbg("wait failed result %d", res); + retval = -1; + } + + if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0)) { + dbg("callout program status 0x%x", status); + retval = -1; + } + } + return retval; +} + static int get_attr(struct sysfs_class_device *class_dev, struct device_attr *attr) { struct list_head *tmp; @@ -587,6 +699,26 @@ label_found: goto done; break; } + case CALLOUT: + { + char value[ID_SIZE]; + + if (exec_callout(dev, value, sizeof(value))) + continue; + if (strncmp(value, dev->id, sizeof(value)) != 0) + continue; + strcpy(attr->name, dev->attr.name); + if (dev->attr.mode != 0) { + attr->mode = dev->attr.mode; + strcpy(attr->owner, dev->attr.owner); + strcpy(attr->group, dev->attr.group); + } + dbg("device callout '%s' becomes '%s' - owner = %s, group = %s, mode = %#o", + dev->id, attr->name, + dev->attr.owner, dev->attr.group, dev->attr.mode); + goto done; + break; + } case REPLACE: if (strcmp(dev->kernel_name, class_dev->name) != 0) continue; diff --git a/namedev.h b/namedev.h index d986a237..1f535c4c 100644 --- a/namedev.h +++ b/namedev.h @@ -40,6 +40,7 @@ enum config_type { NUMBER = 2, TOPOLOGY = 3, REPLACE = 4, + CALLOUT = 5, }; #define BUS_SIZE 30 @@ -60,6 +61,7 @@ struct config_device { char id[ID_SIZE]; char place[PLACE_SIZE]; char kernel_name[NAME_SIZE]; + char exec_program[FILE_SIZE]; /* what to set the device to */ struct device_attr attr; diff --git a/udev.c b/udev.c index 6e7ac251..0aba8c4b 100644 --- a/udev.c +++ b/udev.c @@ -52,13 +52,19 @@ static char *get_device(void) return device; } -int main(int argc, char *argv[]) +char **main_argv; +char **main_envp; + +int main(int argc, char **argv, char **envp) { char *action; char *device; char *subsystem; int retval = -EINVAL; + main_argv = argv; + main_envp = envp; + if (argc != 2) { dbg ("unknown number of arguments"); goto exit; diff --git a/udev.h b/udev.h index 590a8ed0..e9fc2e46 100644 --- a/udev.h +++ b/udev.h @@ -57,5 +57,7 @@ struct device_attr { extern int udev_add_device(char *device, char *subsystem); extern int udev_remove_device(char *device, char *subsystem); +extern char **main_argv; +extern char **main_envp; #endif -- 2.39.5