From 77725291efd609339cc560bec646782bc09ffb90 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Wed, 11 Apr 2018 00:04:33 +0200 Subject: [PATCH] Make line buffer static, move error reporting to rdline - Expose rdline_t struct and move a lot of extra processing to rdline code - Make line buffer statically allocated - Simplify rdsvc code Signed-off-by: David Oberhollenzer --- lib/include/util.h | 48 ++++++++--- lib/src/rdline.c | 106 +++++++++++++------------ lib/src/rdsvc.c | 193 ++++++++++++++++++++------------------------- lib/src/unescape.c | 1 + 4 files changed, 178 insertions(+), 170 deletions(-) diff --git a/lib/include/util.h b/lib/include/util.h index a9d111b..c13b942 100644 --- a/lib/include/util.h +++ b/lib/include/util.h @@ -36,13 +36,40 @@ typedef struct { } enum_map_t; +typedef struct { + int fd; /* input file descriptor */ + const char *argstr; /* if not NULL, read from this instead */ + + const char *filename; /* input file name */ + size_t lineno; /* current line number */ + + size_t i; /* buffer offset */ + char buffer[256]; /* current line, null-terminated */ + + int argc; + const char *const *argv; + + bool string; /* inside a string? */ + bool escape; /* reading an escape sequence? */ + bool comment; /* inside a comment */ +} rdline_t; + + /* - Read from fd until end-of-file or a line feed is encountered. + Initialize the config line scanner. - Returns NULL with errno set on failure. Returns NULL with errno - cleared if end-of-file is reached. + The scanner reads from the provided fd. The filename is used for + error reporting. An argument count and vector can be set for argument + substitution in rdline. +*/ +void rdline_init(rdline_t *t, int fd, const char *filename, + int argc, const char *const *argv); - The line must be deallocated with free(). +/* + Read from file until end-of-file or a line feed is encountered. + + Returns -1 on failure, +1 if end of file was reached, + 0 if data was read successfully. The following transformations are applied: - Space characters are replaced with regular white space characters. @@ -53,19 +80,18 @@ typedef struct { - If a '"' is encounterd, the above rules are disabled, until a after the matching '"' is read. A '"' can be escaped by preceeding it with a backslash. - - If a second, coresponding '"' is not found, processing fails with - errno set to EILSEQ. + - If a second, coresponding '"' is not found, processing fails. - If a '%' character is encountered, the next character is expected to be a single digit index into argv. If it is not a digit or - outside the bounds set by argc, processing fails and sets errno - to EINVAL. On success, the argv value is inserted and processed - as described above. + outside the bounds set by argc, processing fails. On success, + the argv value is inserted and processed as described above. - A '%' character can be escaped by writing '%%' or, if inside a double quite string, by writing \%. - An attempt to use such an indexed argument inside an argument - expansion, results in failure with errno set to ELOOP. + expansion, results in failure. + - If the resulting line is empty, processing is restarted. */ -char *rdline(int fd, int argc, const char *const *argv); +int rdline(rdline_t *t); /* Remove double quotes ('"') from a string and substitute escape diff --git a/lib/src/rdline.c b/lib/src/rdline.c index 18c9c85..47a9d2a 100644 --- a/lib/src/rdline.c +++ b/lib/src/rdline.c @@ -20,22 +20,10 @@ #include #include #include +#include #include "util.h" -typedef struct { - int fd; /* input file descriptor */ - const char *argstr; /* if not NULL, read from this instead */ - - size_t i; /* buffer offset */ - size_t bufsiz; /* buffer size */ - char *buffer; - - bool string; /* inside a string? */ - bool escape; /* reading an escape sequence? */ - bool comment; /* inside a comment */ -} rdline_t; - static int rdline_getc(rdline_t *t) { int ret; @@ -69,9 +57,6 @@ out: static int rdline_append(rdline_t *t, int c) { - size_t newsz; - char *new; - if (t->comment) { if (c != '\0') return 0; @@ -102,67 +87,88 @@ static int rdline_append(rdline_t *t, int c) t->i -= 1; } - if (t->i == t->bufsiz) { - newsz = t->bufsiz ? t->bufsiz * 2 : 16; - new = realloc(t->buffer, newsz); - - if (new == NULL) - return -1; - - t->buffer = new; - t->bufsiz = newsz; - } + if (t->i == sizeof(t->buffer)) + return -1; t->buffer[t->i++] = c; return 0; } -char *rdline(int fd, int argc, const char *const *argv) +void rdline_init(rdline_t *t, int fd, const char *filename, + int argc, const char *const *argv) { - rdline_t rd; - int c, ret; + memset(t, 0, sizeof(*t)); + t->fd = fd; + t->filename = filename; + t->argc = argc; + t->argv = argv; +} - memset(&rd, 0, sizeof(rd)); - rd.fd = fd; +int rdline(rdline_t *t) +{ + const char *errstr; + int c; +retry: + t->i = 0; + t->argstr = NULL; + t->string = t->escape = t->comment = false; + t->lineno += 1; do { - c = rdline_getc(&rd); - if (c < 0) + errno = 0; + c = rdline_getc(t); + if (c < 0) { + if (errno == 0) + return 1; + errstr = strerror(errno); goto fail; - if (c == 0 && rd.string) { - errno = EILSEQ; + } + if (c == 0 && t->string) { + errstr = "missing \""; goto fail; } if (c == '%') { - c = rdline_getc(&rd); - if (c == 0) - errno = EILSEQ; - if (c <= 0) + c = rdline_getc(t); + if (c == 0) { + errstr = "unexpected end of line after '%%'"; goto fail; + } + if (c < 0) { + errstr = strerror(errno); + goto fail; + } if (c != '%') { - if (!isdigit(c) || (c - '0') >= argc) { - errno = EINVAL; + if (!isdigit(c)) { + errstr = "exptected digit after '%%'"; goto fail; } - if (rd.argstr != NULL) { - errno = ELOOP; + if ((c - '0') >= t->argc) { + errstr = "argument out of range"; goto fail; } - rd.argstr = argv[c - '0']; + if (t->argstr != NULL) { + errstr = "recursive argument " + "expansion"; + goto fail; + } + t->argstr = t->argv[c - '0']; continue; } } - if (rdline_append(&rd, c)) + if (rdline_append(t, c)) { + errstr = "line too long"; goto fail; + } } while (c != '\0'); - return rd.buffer; + if (t->buffer[0] == '\0') + goto retry; + + return 0; fail: - ret = errno; - free(rd.buffer); - errno = ret; - return NULL; + fprintf(stderr, "%s: %zu: %s\n", t->filename, t->lineno, errstr); + return -1; } diff --git a/lib/src/rdsvc.c b/lib/src/rdsvc.c index 29c9019..e911724 100644 --- a/lib/src/rdsvc.c +++ b/lib/src/rdsvc.c @@ -28,17 +28,17 @@ #include "service.h" #include "util.h" -static int try_unescape(char *arg, const char *filename, size_t lineno) +static int try_unescape(char *arg, rdline_t *rd) { if (unescape(arg)) { fprintf(stderr, "%s: %zu: malformed string constant\n", - filename, lineno); + rd->filename, rd->lineno); return -1; } return 0; } -static char **try_split_argv(char *str, const char *filename, size_t lineno) +static char **try_split_argv(char *str, rdline_t *rd) { char **argv = split_argv(str); @@ -46,11 +46,11 @@ static char **try_split_argv(char *str, const char *filename, size_t lineno) switch (errno) { case EINVAL: fprintf(stderr, "%s: %zu: malformed string constant\n", - filename, lineno); + rd->filename, rd->lineno); break; default: - fprintf(stderr, "%s: %zu: %s\n", filename, lineno, - strerror(errno)); + fprintf(stderr, "%s: %zu: %s\n", + rd->filename, rd->lineno, strerror(errno)); break; } } @@ -58,43 +58,56 @@ static char **try_split_argv(char *str, const char *filename, size_t lineno) return argv; } -static int svc_desc(service_t *svc, char *arg, - const char *filename, size_t lineno) +static char *try_strdup(const char *str, rdline_t *rd) { - if (try_unescape(arg, filename, lineno)) - return -1; - svc->desc = arg; - return 0; + char *out = strdup(str); + + if (out == NULL) { + fprintf(stderr, "%s: %zu: out of memory\n", + rd->filename, rd->lineno); + } + return out; } -static int svc_tty(service_t *svc, char *arg, - const char *filename, size_t lineno) +static int svc_desc(service_t *svc, char *arg, rdline_t *rd) { - if (try_unescape(arg, filename, lineno)) + if (try_unescape(arg, rd)) return -1; - svc->ctty = arg; - return 0; + svc->desc = try_strdup(arg, rd); + return svc->desc == NULL ? -1 : 0; } -static int svc_exec(service_t *svc, char *arg, - const char *filename, size_t lineno) +static int svc_tty(service_t *svc, char *arg, rdline_t *rd) +{ + if (try_unescape(arg, rd)) + return -1; + svc->ctty = try_strdup(arg, rd); + return svc->ctty == NULL ? -1 : 0; +} + +static int svc_exec(service_t *svc, char *arg, rdline_t *rd) { exec_t *e, *end; - char **argv; - - argv = try_split_argv(arg, filename, lineno); - if (argv == NULL) - return -1; e = calloc(1, sizeof(*e)); if (e == NULL) { - fprintf(stderr, "%s: %zu: out of memory\n", filename, lineno); - free(argv); + fprintf(stderr, "%s: %zu: out of memory\n", + rd->filename, rd->lineno); return -1; } - e->argv = argv; - e->raw_argv = arg; + e->raw_argv = try_strdup(arg, rd); + if (e->raw_argv == NULL) { + free(e); + return -1; + } + + e->argv = try_split_argv(e->raw_argv, rd); + if (e->argv == NULL) { + free(e->raw_argv); + free(e); + return -1; + } if (svc->exec == NULL) { svc->exec = e; @@ -106,47 +119,50 @@ static int svc_exec(service_t *svc, char *arg, return 0; } -static int svc_before(service_t *svc, char *arg, - const char *filename, size_t lineno) +static int svc_before(service_t *svc, char *arg, rdline_t *rd) { if (svc->before != NULL) { fprintf(stderr, "%s: %zu: 'before' dependencies respecified\n", - filename, lineno); + rd->filename, rd->lineno); return -1; } - svc->before = try_split_argv(arg, filename, lineno); + svc->raw_before = try_strdup(arg, rd); + if (svc->raw_before == NULL) + return -1; + + svc->before = try_split_argv(svc->raw_before, rd); if (svc->before == NULL) return -1; - svc->raw_before = arg; return 0; } -static int svc_after(service_t *svc, char *arg, - const char *filename, size_t lineno) +static int svc_after(service_t *svc, char *arg, rdline_t *rd) { if (svc->after != NULL) { fprintf(stderr, "%s: %zu: 'after' dependencies respecified\n", - filename, lineno); + rd->filename, rd->lineno); return -1; } - svc->after = try_split_argv(arg, filename, lineno); + svc->raw_after = try_strdup(arg, rd); + if (svc->raw_after == NULL) + return -1; + + svc->after = try_split_argv(svc->raw_after, rd); if (svc->after == NULL) return -1; - svc->raw_after = arg; return 0; } -static int svc_type(service_t *svc, char *arg, - const char *filename, size_t lineno) +static int svc_type(service_t *svc, char *arg, rdline_t *rd) { char **args; int i, type; - args = try_split_argv(arg, filename, lineno); + args = try_split_argv(arg, rd); if (args == NULL) return -1; @@ -155,7 +171,7 @@ static int svc_type(service_t *svc, char *arg, if (type == -1) { fprintf(stderr, "%s: %zu: unknown service type '%s'\n", - filename, lineno, args[0]); + rd->filename, rd->lineno, args[0]); free(args); return -1; } @@ -183,48 +199,45 @@ static int svc_type(service_t *svc, char *arg, /* fall-through */ default: fprintf(stderr, "%s: %zu: unexpected extra arguments " - "for type '%s'\n", filename, lineno, arg); + "for type '%s'\n", + rd->filename, rd->lineno, arg); return -1; } } svc->type = type; free(args); - free(arg); return 0; fail_limit: fprintf(stderr, "%s: %zu: expected 'limit ' after 'respawn'\n", - filename, lineno); + rd->filename, rd->lineno); free(args); return -1; } -static int svc_target(service_t *svc, char *arg, - const char *filename, size_t lineno) +static int svc_target(service_t *svc, char *arg, rdline_t *rd) { int target; - if (try_unescape(arg, filename, lineno)) + if (try_unescape(arg, rd)) return -1; target = svc_target_from_string(arg); if (target == -1) { fprintf(stderr, "%s: %zu: unknown service target '%s'\n", - filename, lineno, arg); + rd->filename, rd->lineno, arg); return -1; } svc->target = target; - free(arg); return 0; } static const struct svc_param { const char *key; - int (*handle)(service_t *svc, char *arg, - const char *filename, size_t lineno); + int (*handle)(service_t *svc, char *arg, rdline_t *rd); } svc_params[] = { { "description", svc_desc }, { "exec", svc_exec }, @@ -235,49 +248,15 @@ static const struct svc_param { { "after", svc_after }, }; - -static char *get_line(int fd, const char *filename, size_t *lineno, - int argc, const char *const *args) +static int splitkv(rdline_t *rd, char **k, char **v) { - const char *error; - char *line; - int ret; -retry: - errno = 0; - line = rdline(fd, argc, args); - ret = errno; - - if (line == NULL && errno != 0) { - switch (errno) { - case EINVAL: error = "error in argument expansion"; break; - case ELOOP: error = "recursive argument expansion"; break; - case EILSEQ: error = "missing \""; break; - default: error = strerror(errno); break; - } - - fprintf(stderr, "%s: %zu: %s\n", filename, *lineno, error); - } - - if (line != NULL && strlen(line) == 0) { - free(line); - (*lineno) += 1; - goto retry; - } - - errno = ret; - return line; -} - -static int splitkv(const char *filename, size_t lineno, - char *line, char **k, char **v) -{ - char *key = line, *value = line; + char *key = rd->buffer, *value = rd->buffer; while (*value != ' ' && *value != '\0') { if (!isalpha(*value)) { fprintf(stderr, "%s: %zu: unexpected '%c' in keyword\n", - filename, lineno, *value); + rd->filename, rd->lineno, *value); return -1; } ++value; @@ -285,7 +264,7 @@ static int splitkv(const char *filename, size_t lineno, if (*value != ' ') { fprintf(stderr, "%s: %zu: expected argument after '%s'\n", - filename, lineno, key); + rd->filename, rd->lineno, key); return -1; } @@ -296,8 +275,7 @@ static int splitkv(const char *filename, size_t lineno, return 0; } -static const struct svc_param *find_param(const char *filename, size_t lineno, - const char *name) +static const struct svc_param *find_param(rdline_t *rd, const char *name) { size_t i; @@ -307,19 +285,20 @@ static const struct svc_param *find_param(const char *filename, size_t lineno, } fprintf(stderr, "%s: %zu: unknown keyword '%s'\n", - filename, lineno, name); + rd->filename, rd->lineno, name); return NULL; } service_t *rdsvc(int dirfd, const char *filename) { - char *line = NULL, *key, *value; const struct svc_param *p; const char *arg, *args[1]; service_t *svc = NULL; - size_t argc, lineno; - int fd; + char *key, *value; + size_t argc; + rdline_t rd; + int fd, ret; fd = openat(dirfd, filename, O_RDONLY); if (fd < 0) { @@ -335,6 +314,8 @@ service_t *rdsvc(int dirfd, const char *filename) argc = 0; } + rdline_init(&rd, fd, filename, argc, args); + svc = calloc(1, sizeof(*svc)); if (svc == NULL) goto fail_oom; @@ -348,32 +329,26 @@ service_t *rdsvc(int dirfd, const char *filename) if (svc->name == NULL) goto fail_oom; - for (lineno = 1; ; ++lineno) { - line = get_line(fd, filename, &lineno, argc, args); - if (line == NULL) { - if (errno == 0) - break; - goto fail; - } - - if (splitkv(filename, lineno, line, &key, &value)) + while ((ret = rdline(&rd)) == 0) { + if (splitkv(&rd, &key, &value)) goto fail; - p = find_param(filename, lineno, key); + p = find_param(&rd, key); if (p == NULL) goto fail; - memmove(line, value, strlen(value) + 1); - if (p->handle(svc, line, filename, lineno)) + if (p->handle(svc, value, &rd)) goto fail; } + if (ret < 0) + goto fail; + close(fd); return svc; fail_oom: fputs("out of memory\n", stderr); fail: - free(line); delsvc(svc); close(fd); return NULL; diff --git a/lib/src/unescape.c b/lib/src/unescape.c index 7508e2f..ea5c9e2 100644 --- a/lib/src/unescape.c +++ b/lib/src/unescape.c @@ -59,6 +59,7 @@ int unescape(char *src) case 't': c = '\t'; break; case '\\': case '"': + case '%': break; case 'x': c = 0;