Re: [PATCH v2] lib/igt_rc: Introduce generic config parser

hello, friendly ping on this

On Mon, Jul 20, 2026 at 2:50 PM Mark Yacoub <[email protected]> wrote:

> Currently, libraries like unigraf explicitly rely on GKeyFile
> for reading configuration from .igtrc. Android builds do not
> natively supply glib, meaning these tools cannot be cleanly
> compiled.
>
> This patch abstracts config parsing into a dedicated `igt_rc` module.
> On standard Linux, `igt_rc` seamlessly wraps glib's native methods.
> On Android environments, `igt_rc` natively parses `.igtrc` using
> a stripped-down, thread-safe linked-list implementation
> (lib/android/igt_rc.c).
>
> v2:
>  - Drop the GKeyFile abstraction fakes from android/glib.h (Review
> feedback)
>  - Introduce a generic wrapper (igt_rc.h) instead of modifying glib.h.
>  - Provide a pure glib backend for Linux to avoid regressions.
>  - Isolate Android parsing implementation cleanly into
> lib/android/igt_rc.c.
> ---
>  lib/android/igt_rc.c         | 172 +++++++++++++++++++++++++++++++++++
>  lib/igt_rc.c                 |  61 +++++++++++++
>  lib/igt_rc.h                 |   5 +
>  lib/meson.build              |   1 +
>  lib/vendor/unigraf/unigraf.c |  92 ++++++++-----------
>  5 files changed, 279 insertions(+), 52 deletions(-)
>  create mode 100644 lib/android/igt_rc.c
>  create mode 100644 lib/igt_rc.c
>
> diff --git a/lib/android/igt_rc.c b/lib/android/igt_rc.c
> new file mode 100644
> index 000000000..6d9b348f7
> --- /dev/null
> +++ b/lib/android/igt_rc.c
> @@ -0,0 +1,172 @@
> +#include "igt_rc.h"
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <strings.h>
> +#include <ctype.h>
> +#include <pthread.h>
> +
> +struct igt_key_entry {
> +       char *group;
> +       char *key;
> +       char *value;
> +       struct igt_key_entry *next;
> +};
> +
> +static struct igt_key_entry *rc_entries = NULL;
> +static pthread_once_t rc_once_control = PTHREAD_ONCE_INIT;
> +
> +static char *trim_whitespace(char *str)
> +{
> +       char *end;
> +
> +       while (isspace((unsigned char)*str))
> +               str++;
> +
> +       if (*str == 0)
> +               return str;
> +
> +       end = str + strlen(str) - 1;
> +       while (end > str && isspace((unsigned char)*end))
> +               end--;
> +
> +       end[1] = '\0';
> +       return str;
> +}
> +
> +static void load_igtrc_once(void)
> +{
> +       FILE *fp;
> +       char *line = NULL;
> +       size_t len = 0;
> +       ssize_t read;
> +       char *current_group = NULL;
> +       struct igt_key_entry *tail = NULL;
> +       char path[512];
> +
> +       snprintf(path, sizeof(path), "%s/.igtrc", "/data/local/tmp/igt");
> +
> +       fp = fopen(path, "r");
> +       if (!fp)
> +               return;
> +
> +       while ((read = getline(&line, &len, fp)) != -1) {
> +               char *trimmed = trim_whitespace(line);
> +
> +               if (*trimmed == '\0' || *trimmed == '#' || *trimmed == ';')
> +                       continue;
> +
> +               if (trimmed[0] == '[' && trimmed[strlen(trimmed) - 1] ==
> ']') {
> +                       free(current_group);
> +                       trimmed[strlen(trimmed) - 1] = '\0';
> +                       current_group = strdup(trimmed + 1);
> +                       continue;
> +               }
> +
> +               if (current_group) {
> +                       char *eq = strchr(trimmed, '=');
> +
> +                       if (eq) {
> +                               char *key;
> +                               char *value;
> +                               struct igt_key_entry *entry;
> +
> +                               *eq = '\0';
> +                               key = trim_whitespace(trimmed);
> +                               value = trim_whitespace(eq + 1);
> +
> +                               entry = calloc(1, sizeof(*entry));
> +                               entry->group = strdup(current_group);
> +                               entry->key = strdup(key);
> +                               entry->value = strdup(value);
> +                               entry->next = NULL;
> +
> +                               if (!rc_entries) {
> +                                       rc_entries = entry;
> +                                       tail = entry;
> +                               } else {
> +                                       tail->next = entry;
> +                                       tail = entry;
> +                               }
> +                       }
> +               }
> +       }
> +
> +       free(current_group);
> +       free(line);
> +       fclose(fp);
> +}
> +
> +__attribute__((destructor))
> +static void free_igtrc(void)
> +{
> +       struct igt_key_entry *curr, *next;
> +
> +       curr = rc_entries;
> +       while (curr) {
> +               next = curr->next;
> +               free(curr->group);
> +               free(curr->key);
> +               free(curr->value);
> +               free(curr);
> +               curr = next;
> +       }
> +       rc_entries = NULL;
> +}
> +
> +char *igt_rc_get_string(const char *group_name, const char *key)
> +{
> +       char *last_match = NULL;
> +       struct igt_key_entry *curr;
> +
> +       pthread_once(&rc_once_control, load_igtrc_once);
> +
> +       curr = rc_entries;
> +       while (curr) {
> +               if (strcmp(curr->group, group_name) == 0 &&
> strcmp(curr->key, key) == 0)
> +                       last_match = curr->value;
> +               curr = curr->next;
> +       }
> +
> +       return last_match ? strdup(last_match) : NULL;
> +}
> +
> +bool igt_rc_get_boolean(const char *group_name, const char *key, bool
> *out)
> +{
> +       char *val = igt_rc_get_string(group_name, key);
> +
> +       if (!val)
> +               return false;
> +
> +       if (strcasecmp(val, "true") == 0 || strcmp(val, "1") == 0) {
> +               *out = true;
> +       } else if (strcasecmp(val, "false") == 0 || strcmp(val, "0") == 0)
> {
> +               *out = false;
> +       } else {
> +               free(val);
> +               return false;
> +       }
> +
> +       free(val);
> +       return true;
> +}
> +
> +int igt_rc_get_integer(const char *group_name, const char *key, int *out)
> +{
> +       char *val = igt_rc_get_string(group_name, key);
> +       char *endptr;
> +       long lval;
> +
> +       if (!val)
> +               return false;
> +
> +       lval = strtol(val, &endptr, 10);
> +       if (*endptr != '\0') {
> +               free(val);
> +               return false;
> +       }
> +
> +       *out = (int)lval;
> +       free(val);
> +       return true;
> +}
> diff --git a/lib/igt_rc.c b/lib/igt_rc.c
> new file mode 100644
> index 000000000..31eb07bc0
> --- /dev/null
> +++ b/lib/igt_rc.c
> @@ -0,0 +1,61 @@
> +#include "igt_rc.h"
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <strings.h>
> +#include <ctype.h>
> +
> +#include <glib.h>
> +
> +char *igt_rc_get_string(const char *group_name, const char *key)
> +{
> +       GError *error = NULL;
> +       char *val;
> +
> +       if (!igt_key_file)
> +               return NULL;
> +
> +       val = g_key_file_get_string(igt_key_file, group_name, key, &error);
> +       if (error) {
> +               g_error_free(error);
> +               return NULL;
> +       }
> +
> +       return val;
> +}
> +
> +bool igt_rc_get_boolean(const char *group_name, const char *key, bool
> *out)
> +{
> +       GError *error = NULL;
> +       gboolean val;
> +
> +       if (!igt_key_file)
> +               return false;
> +
> +       val = g_key_file_get_boolean(igt_key_file, group_name, key,
> &error);
> +       if (error) {
> +               g_error_free(error);
> +               return false;
> +       }
> +
> +       *out = val;
> +       return true;
> +}
> +
> +int igt_rc_get_integer(const char *group_name, const char *key, int *out)
> +{
> +       GError *error = NULL;
> +       int val;
> +
> +       if (!igt_key_file)
> +               return false;
> +
> +       val = g_key_file_get_integer(igt_key_file, group_name, key,
> &error);
> +       if (error) {
> +               g_error_free(error);
> +               return false;
> +       }
> +
> +       *out = val;
> +       return true;
> +}
> diff --git a/lib/igt_rc.h b/lib/igt_rc.h
> index d871b3b26..a0942f8d0 100644
> --- a/lib/igt_rc.h
> +++ b/lib/igt_rc.h
> @@ -1,3 +1,4 @@
> +#include <stdbool.h>
>  /*
>   * Copyright © 2017 Intel Corporation
>   *
> @@ -33,4 +34,8 @@
>
>  extern GKeyFile *igt_key_file;
>
> +char *igt_rc_get_string(const char *group_name, const char *key);
> +bool igt_rc_get_boolean(const char *group_name, const char *key, bool
> *out);
> +int igt_rc_get_integer(const char *group_name, const char *key, int *out);
> +
>  #endif /* IGT_RC_H */
> diff --git a/lib/meson.build b/lib/meson.build
> index 8db9fffde..20c2f34d7 100644
> --- a/lib/meson.build
> +++ b/lib/meson.build
> @@ -97,6 +97,7 @@ lib_sources = [
>         'igt_kms.c',
>         'igt_fb.c',
>         'igt_core.c',
> +       'igt_rc.c',
>         'igt_dir.c',
>         'igt_draw.c',
>         'igt_list.c',
> diff --git a/lib/vendor/unigraf/unigraf.c b/lib/vendor/unigraf/unigraf.c
> index 30ee3c72b..64268db34 100644
> --- a/lib/vendor/unigraf/unigraf.c
> +++ b/lib/vendor/unigraf/unigraf.c
> @@ -364,7 +364,6 @@ int unigraf_get_connector_id_by_stream(int drm_fd, int
> stream_id)
>  bool unigraf_open_device(int drm_fd)
>  {
>         TSI_RESULT r;
> -       GError *cfg_error = NULL;
>         char *cfg_device = NULL;
>         char *cfg_role = NULL;
>         char *cfg_input = NULL;
> @@ -382,63 +381,52 @@ bool unigraf_open_device(int drm_fd)
>
>         unigraf_init();
>
> -       if (igt_key_file) {
> -               cfg_device = g_key_file_get_string(igt_key_file,
> UNIGRAF_CONFIG_GROUP,
> -
> UNIGRAF_CONFIG_DEVICE_NAME, &cfg_error);
> -               if (cfg_error) {
> -                       unigraf_debug("No device name configured, uses
> first device available.\n");
> -                       cfg_device = NULL;
> -               }
> +       cfg_device = igt_rc_get_string(UNIGRAF_CONFIG_GROUP,
> +                                      UNIGRAF_CONFIG_DEVICE_NAME);
> +       if (!cfg_device) {
> +               unigraf_debug("No device name configured, uses first
> device available.\n");
> +               cfg_device = NULL;
> +       }
>
> -               cfg_error = NULL;
> -               cfg_role = g_key_file_get_string(igt_key_file,
> UNIGRAF_CONFIG_GROUP,
> -
> UNIGRAF_CONFIG_DEVICE_ROLE, &cfg_error);
> -               if (cfg_error) {
> -                       unigraf_debug("No device role configured.\n");
> -                       cfg_role = NULL;
> -               }
> +       cfg_role = igt_rc_get_string(UNIGRAF_CONFIG_GROUP,
> +                                    UNIGRAF_CONFIG_DEVICE_ROLE);
> +       if (!cfg_role) {
> +               unigraf_debug("No device role configured.\n");
> +               cfg_role = NULL;
> +       }
>
> -               cfg_error = NULL;
> -               cfg_input = g_key_file_get_string(igt_key_file,
> UNIGRAF_CONFIG_GROUP,
> -
>  UNIGRAF_CONFIG_INPUT_NAME, &cfg_error);
> -               if (cfg_error) {
> -                       unigraf_debug("No input name configured.\n");
> -                       cfg_input = NULL;
> -               }
> +       cfg_input = igt_rc_get_string(UNIGRAF_CONFIG_GROUP,
> +                                     UNIGRAF_CONFIG_INPUT_NAME);
> +       if (!cfg_input) {
> +               unigraf_debug("No input name configured.\n");
> +               cfg_input = NULL;
> +       }
>
> -               cfg_error = NULL;
> -               unigraf_connector_name =
> g_key_file_get_string(igt_key_file, UNIGRAF_CONFIG_GROUP,
> -
> UNIGRAF_CONFIG_CONNECTOR_NAME,
> -                                                              &cfg_error);
> -               if (cfg_error) {
> -                       unigraf_debug("No connector name configured, will
> autodetect.\n");
> -                       unigraf_connector_name = NULL;
> -               }
> +       unigraf_connector_name = igt_rc_get_string(UNIGRAF_CONFIG_GROUP,
> +
> UNIGRAF_CONFIG_CONNECTOR_NAME);
> +       if (!unigraf_connector_name) {
> +               unigraf_debug("No connector name configured, will
> autodetect.\n");
> +               unigraf_connector_name = NULL;
> +       }
>
> -               cfg_error = NULL;
> -               cfg_edid_name = g_key_file_get_string(igt_key_file,
> UNIGRAF_CONFIG_GROUP,
> -
>  UNIGRAF_CONFIG_EDID_NAME, &cfg_error);
> -               if (cfg_error) {
> -                       unigraf_debug("No default EDID set, use IGT
> default.\n");
> -                       cfg_edid_name = NULL;
> -               }
> +       cfg_edid_name = igt_rc_get_string(UNIGRAF_CONFIG_GROUP,
> +                                         UNIGRAF_CONFIG_EDID_NAME);
> +       if (!cfg_edid_name) {
> +               unigraf_debug("No default EDID set, use IGT default.\n");
> +               cfg_edid_name = NULL;
> +       }
>
> -               cfg_error = NULL;
> -               unigraf_crc = g_key_file_get_boolean(igt_key_file,
> UNIGRAF_CONFIG_GROUP,
> -
> UNIGRAF_CONFIG_USE_CRC_NAME, &cfg_error);
> -               if (cfg_error) {
> -                       unigraf_debug("CRC usage not configured, using
> unigraf CRC.\n");
> -                       unigraf_crc = true;
> -               }
> +       if (!igt_rc_get_boolean(UNIGRAF_CONFIG_GROUP,
> +                               UNIGRAF_CONFIG_USE_CRC_NAME,
> &unigraf_crc)) {
> +               unigraf_debug("CRC usage not configured, using unigraf
> CRC.\n");
> +               unigraf_crc = true;
> +       }
>
> -               cfg_error = NULL;
> -               unigraf_stream_count =
> g_key_file_get_integer(igt_key_file, UNIGRAF_CONFIG_GROUP,
> -
>  UNIGRAF_CONFIG_MST_STREAM_COUNT,
> -                                                             &cfg_error);
> -               if (cfg_error) {
> -                       unigraf_debug("MST usage not configured, using
> SST.\n");
> -                       unigraf_stream_count = 0;
> -               }
> +       if (!igt_rc_get_integer(UNIGRAF_CONFIG_GROUP,
> +                               UNIGRAF_CONFIG_MST_STREAM_COUNT,
> +                               &unigraf_stream_count)) {
> +               unigraf_debug("MST usage not configured, using SST.\n");
> +               unigraf_stream_count = 0;
>         }
>
>         unigraf_assert(TSIX_DEV_RescanDevices(0, TSI_DEVCAP_VIDEO_CAPTURE,
> 0));
> --
> 2.55.0.229.g6434b31f56-goog
>
>